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Knight Owl EWA eyepieces and Pentax 65 (1 Viewer)

Can Popper,

I did receive the Seibert 19 mm yesterday in the mail. Interesting eyepiece. The two things that I immediately noticed were the size and the weight. It is noticeably wider than the Knight Owl EWAs but shorter and significantly lighter. It almost feels like there is nothing to it.

Now, as far as an image comparison, at close range on the backyard feeders I honestly could not tell much of a difference between it and the 20 mm Knight Owl EWA except for maybe edge distortion. The 20 mm EWA seemed to offer a more relaxed view possibly because of the larger diamter ocular lens and maybe a tad more eye relief? However, when I took both eyepieces out to the local lake to compare them at longer distances the Seibert 19 mm started to differentiate itself. I believe it showed slightly better contrast and brightness with a noticeably flatter image.

Digiscoping results didn't improve much though despite my best efforts. That leads me to wonder if I should opt for a lower magnification eyepiece with my 65 mm Pentax...something in the 24-34 mm range possibly...which would give me a magnification range anywhere from 10x to 16x depending on which size I decide on. Considering you have the 24 mm Seibert Ultra and were in the process of getting the Seibert 35 mm Performance then what are your thoughts on this issue? Would I be better served for digiscoping with a lower mag. eyepiece? Would another Seibert be the best route to follow or are there other 1.25 inch eyepieces out there that I should consider in that price range or possibly under?

Thank you.
 
Hi Frank,
I've been reading your threads on the digiscoping forum :)

I have a few thoughts knocking around my head. There are three pieces to your digiscoping endeavor. The scope, eyepiece, and camera. I think maybe we should make sure each of the components is working the way it should.

1. For the scope, have you star tested it? Use the Siebert and EWAs and point the scope at the stars on a clear night. Make sure each star comes through as a pin point of light. In other scope threads, I've read about good samples and bad samples so let's make sure yours is not a bad sample.

2. For the eyepiece, yes, I do find the lower the magnification, the better and sharper the image. However, the tradeoff is more vignetting since the FOV significantly falls off when the power falls below 24mm. I think the increase sharpness does come from the large exit pupil. Like our eyes, our camera also have a maximum "pupil" size. That would be the maximum width of our camera's iris.

For my Fuji F10, it would be about 5mm. Assuming your camera is the same, then a 30mm eyepiece would give you a 5mm exit pupil. Maybe you can trade your Ultra 19mm for the Ultra 30mm (28mm if you want a bit wider FOV)? Or if you want to save a bit of money, trade the 19mm for the Performance 32mm and get $50 back.

Another choice would be to go with the Plossl 32mm. However, the plossls do have slightly curved fields, less edge sharpness and less FOV which is why I decided to try out a Siebert 35mm. If you are super crazy, try out the Edmund RKE 28mm. It uses only 3 lenses, has long eyerelief, and is reviewed to be super sharp and bright. However, it only has a 45 degree FOV.

3. Last is your camera itself. Maybe the optical quality of your casio camera is less than optimal. Looking at the specs here: http://www.casio.com/products/Cameras/Exilim_Zoom/EX-Z1000/content/Technical_Specs/, your camera uses 7 lenses in 5 groups. That's alot of glass, IMO. Usually, eyepieces with that much glass with less than optimal coatings have softer images. When added with the additional glass of the spotter plus eyepiece, you will compound the softness. This is also why DSLRs in prime focus mode is way sharper. You get to eliminate the additional glass from the eyepiece and the telephoto lens.

You can try to see if a different camera gives you better results. Maybe bring your setup to a good camera store during non-busy times to mess around. Sonys use Zeiss lenses with awesome coatings. I have a Sony Camcorder with the Zeiss lens and it does look superior to the lens on my Fuji F10. Maybe I'll digiscope with it and post some of the pics here.

FrankD said:
Can Popper,

I did receive the Seibert 19 mm yesterday in the mail. Interesting eyepiece. The two things that I immediately noticed were the size and the weight. It is noticeably wider than the Knight Owl EWAs but shorter and significantly lighter. It almost feels like there is nothing to it.

Now, as far as an image comparison, at close range on the backyard feeders I honestly could not tell much of a difference between it and the 20 mm Knight Owl EWA except for maybe edge distortion. The 20 mm EWA seemed to offer a more relaxed view possibly because of the larger diamter ocular lens and maybe a tad more eye relief? However, when I took both eyepieces out to the local lake to compare them at longer distances the Seibert 19 mm started to differentiate itself. I believe it showed slightly better contrast and brightness with a noticeably flatter image.

Digiscoping results didn't improve much though despite my best efforts. That leads me to wonder if I should opt for a lower magnification eyepiece with my 65 mm Pentax...something in the 24-34 mm range possibly...which would give me a magnification range anywhere from 10x to 16x depending on which size I decide on. Considering you have the 24 mm Seibert Ultra and were in the process of getting the Seibert 35 mm Performance then what are your thoughts on this issue? Would I be better served for digiscoping with a lower mag. eyepiece? Would another Seibert be the best route to follow or are there other 1.25 inch eyepieces out there that I should consider in that price range or possibly under?

Thank you.
 
Can Popper,

Thank you for taking the time to post such a detailed response.

1. Yes, I did use it at night right after I purchased it. The stars seemed to come through as nice pinpoints of light with the Meade 25 mm eyepiece I had used at the time. I did not star test it with either the EWAs or the Seibert yet though.

2. I do like the image of the 19 mm Seibert. It should prove as adequate for digiscoping as my 20 mm EWA. I believe I will keep it as it should be a great all around eyepiece for birding. But, I think I am also going to get either the 24 mm Seibert or the Performance 32 mm. What is the field of view on the latter? (since you mentioned it decreasing at a given size)

3. I hope the camera isn't the case as this is probably the only thing I cannot directly remedy. The two week grace period for returning it ended a week ago. Buying a digital camera which was effective for digiscoping proved difficult for a variety of reasons. Just learning the basics needed for a good digiscoping camera ( eyepiece to camera lens diameter similarity, some manual controls, lack of vignetting, etc...) didn't seem to be enough as you have just illustrated. I have to make the best with what I have in this case. Hopefully the change to a lower magnification eyepiece or maybe further experimentation with the camera's settings will provide better results. One can always hope. ;)

Thank you again for the help. Your responses here and the thread you have posted previously on eyepieces for the Pentaxes have proved invaluable in my education as this point.
 
FrankD said:
Can Popper,

Thank you for taking the time to post such a detailed response.

1. Yes, I did use it at night right after I purchased it. The stars seemed to come through as nice pinpoints of light with the Meade 25 mm eyepiece I had used at the time. I did not star test it with either the EWAs or the Seibert yet though.

2. I do like the image of the 19 mm Seibert. It should prove as adequate for digiscoping as my 20 mm EWA. I believe I will keep it as it should be a great all around eyepiece for birding. But, I think I am also going to get either the 24 mm Seibert or the Performance 32 mm. What is the field of view on the latter? (since you mentioned it decreasing at a given size)

3. I hope the camera isn't the case as this is probably the only thing I cannot directly remedy. The two week grace period for returning it ended a week ago. Buying a digital camera which was effective for digiscoping proved difficult for a variety of reasons. Just learning the basics needed for a good digiscoping camera ( eyepiece to camera lens diameter similarity, some manual controls, lack of vignetting, etc...) didn't seem to be enough as you have just illustrated. I have to make the best with what I have in this case. Hopefully the change to a lower magnification eyepiece or maybe further experimentation with the camera's settings will provide better results. One can always hope. ;)

Thank you again for the help. Your responses here and the thread you have posted previously on eyepieces for the Pentaxes have proved invaluable in my education as this point.
Dear friend Frank D.

I have read some of the threads that you have posted looking for the perfect eyepiece for the pentax 65.....you choose the route of the inexpensive/less expensive eyepieces to try and find the good value/performance ratio ..seems to me that you have purchased a bunch of eyepieces in the low /medium and still not satisfied with the results you are achieving... sometimes the best thing is to buy that premium eyepiece that you wanted...and to be sure that you have the best possible performance for all your needs ,and SAVE time and money....with the investment in eyepieces that you have made already ,you could have bought the Pentax 14 XW and you would have saved money!The best possible eyepiece would have been the short /inexpensive route.Dont let the idea of deffective equipment bother you ,"lemon"stories are not the most usual thing....i have Star tested my pentax 65 and sometimes,the test varies ,as seeing conditions do!! i have performed ,though,perfect tests with it.....the Star test consist basically in achieve focus at a Star (or a tiny reflection of the sun ,by that matter)and bring the image SLIGHTLY IN AND OUT OF FOCUS,OBSERVING THE CONCENTRIC RINGS THAT APPEAR AND THEIR SHAPE....only testing how sharp a given star appear to your eye is not an accurate star test.Look at star test results in the web and test yours ,but only for fun!!!!!!it would only prove that your scope is fine..............!!!!!
 
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The FOV on the Performance 32mm is 50 degrees (I think), about the same as a plossl.

For the Ultra 28, it is 60 degrees. Ultra 24 is 65 degrees.

Basically, what you see with FOV as the magnification gets lower is:

20mm - 70 degree
24mm - 65 degrees
28mm - 60 degrees
30mm - 54 degrees
32mm - 50 degrees
35mm - 47 degrees
40mm - 43 degrees

I originally got the Ultra 24's because I wanted to use it in a binoviewer config. It reviewed really well on Cloudy Nights as a binoviewer eyepiece. However, after I determined that I also wanted an eyepiece that would provide the lowest power and widest field for digiscoping, the Ultra 24mm again fit the bill.

Here are some other thoughts I have on improving the image. If you look at the 3 dove pictures I posted, the one with the darkest exposure compensation is also the sharpest. Maybe we can improve our pictures by intentionally taking them to be darker with a higher negative exposure compensation setting and then brighten them digitally in software.

Another thing I did to improve my picture taking was to have the camera snap 3 pictures in a row when I fire off the 2 seconds timer. Since the bird is usually moving oh so slightly, the 3 rapid fire pictures will have one that is better than the others.

In astronomy, people now use CCDs to take videos of the planets and then use software to merge the multiple frames to produce a better final picture.

Of course, also make sure you are shooting from a stable base. A good solid tripod is important. One thing you can do to reduce scope/camera shake is to shoot the pictures lower to the ground with the tripod legs spread out as much as they can. A higher center of gravity means more scope shake.

I did notice an improvement in my pictures when I went from a cheap eBay tripod to my much heavier and sturdier Orion xHD's.

FrankD said:
Can Popper,

Thank you for taking the time to post such a detailed response.

1. Yes, I did use it at night right after I purchased it. The stars seemed to come through as nice pinpoints of light with the Meade 25 mm eyepiece I had used at the time. I did not star test it with either the EWAs or the Seibert yet though.

2. I do like the image of the 19 mm Seibert. It should prove as adequate for digiscoping as my 20 mm EWA. I believe I will keep it as it should be a great all around eyepiece for birding. But, I think I am also going to get either the 24 mm Seibert or the Performance 32 mm. What is the field of view on the latter? (since you mentioned it decreasing at a given size)

3. I hope the camera isn't the case as this is probably the only thing I cannot directly remedy. The two week grace period for returning it ended a week ago. Buying a digital camera which was effective for digiscoping proved difficult for a variety of reasons. Just learning the basics needed for a good digiscoping camera ( eyepiece to camera lens diameter similarity, some manual controls, lack of vignetting, etc...) didn't seem to be enough as you have just illustrated. I have to make the best with what I have in this case. Hopefully the change to a lower magnification eyepiece or maybe further experimentation with the camera's settings will provide better results. One can always hope. ;)

Thank you again for the help. Your responses here and the thread you have posted previously on eyepieces for the Pentaxes have proved invaluable in my education as this point.
 
mayoayo,

Thank you very much for the help. I am always looking for new perspectives on this issue. I have seen many folks reading these threads but few post. I wonder why? I am sure some folks are just learning as I am but I am sure others have some tidbits of info that would probably help myself and others.

I have read some of the threads that you have posted looking for the perfect eyepiece for the pentax 65.....you choose the route of the inexpensive/less expensive eyepieces to try and find the good value/performance ratio ..seems to me that you have purchased a bunch of eyepieces in the low /medium and still not satisfied with the results you are achieving... sometimes the best thing is to buy that premium eyepiece that you wanted...and to be sure that you have the best possible performance for all your needs ,and SAVE time and money....with the investment in eyepieces that you have made already ,you could have bought the Pentax 14 XW and you would have saved money!

All very true. As always I try to find the best performance versus cost ratio. I bought my main pair of binos, the 8x42 Venturer LXs, for $400 as they were refurbished. I bought the Pentax 65 mm ED A because it has been reviewed to be the equal of the Nikon, Swaro, Zeiss, etc.. of the same objective diameter and yet at a must less expensive cost. The fact that you can tinker with a variety of astronomical eyepieces was just the icing on the cake. Buying the 3 Knight Owl eyepieces was still a good choice in my opinion because it gave me three magnifications at a relatively inexpensive price. My thought at the time was to tinker with digiscoping and these eyepieces. I realize there was going to be a trade-off at some point and my attempts at digiscoping up until now seem to illustrate it.

I bought the Seibert simply because Can Popper, and the Cloudy Nights forum, gave it fairly high praise compared to much more expensive eyepieces. My expectations were that it would work equally well with my scope as one of Pentax's own or a Televue, Panoptic, etc... One of the Seibert's still might assuming a lower magnification size does the trick. I would still probably like a Pentax 20 mm XW but Can Popper pointed out something I did not consider. My current Universal Digiscoping adapter is pretty much maxed out in terms of diameter on these Seiberts. The Pentaxs are even wider and therefore I would have to drop further money for a larger size adapter. Are the Panoptics or Televues smaller?

Thank you again for the help. It is much appreciated.

Can Popper,

Thank you for the information on the fields of view versus eyepiece size chart. I think the 24 mm would work though the 28 mm looks equally attractive. That 28 mm model would give me about 14x by itself. Couple that with a 3x optical zoom on the camera would yield 42x which should be sufficient for moderate range digiscoping. The higher light levels should yield brighter more detailed images. However, the 24 mm might serve equally well though as we are only talking about a difference in exit pupil size of under 1 mm. Assuming my camera's aperture responds to the brighter image accordingly I should get a higher quality digiscoped image.

Here are some other thoughts I have on improving the image. If you look at the 3 dove pictures I posted, the one with the darkest exposure compensation is also the sharpest. Maybe we can improve our pictures by intentionally taking them to be darker with a higher negative exposure compensation setting and then brighten them digitally in software.

Another thing I did to improve my picture taking was to have the camera snap 3 pictures in a row when I fire off the 2 seconds timer. Since the bird is usually moving oh so slightly, the 3 rapid fire pictures will have one that is better than the others.

Most of my photos tend to be a bit on the underexposed side to begin with so you may have something here.

I also have the 3 shot burst function on my camera. I believe it is called continuous high speed. 3 shots in about a second if I remember correctly. I played with this a bit but did not take it seriously at the time in relation to digiscoping.

Of course, also make sure you are shooting from a stable base. A good solid tripod is important. One thing you can do to reduce scope/camera shake is to shoot the pictures lower to the ground with the tripod legs spread out as much as they can. A higher center of gravity means more scope shake.

I did notice an improvement in my pictures when I went from a cheap eBay tripod to my much heavier and sturdier Orion xHD's.

I went the expensive route on this one and opted for the Manfrotto 3001BN legs and the 3130 head. However, I have been keeping the legs compacted while extending the center shaft for height adjustment while I am sitting in the chair to take the pics. I could keep the center column tight up against the leg connection and just extend the legs if you feel it would make a difference.

Again, much thanks for the thoughtful suggestions.
 
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The Televues are smaller eyepieces than the Pentaxes and should fit your existing adapapter. In my opinion ( I have the 25 mm and 32 mm Plossls ) they are similar quality to the Swarovskis.
Don't forget that 3 x optical is not necessarly 3x in 35 mm terms as most digicams start measuring at the wide end . Most are 35 - 115 mm lens (approx ) which equates to 0.7 - 2.3 x optical (50 mm is considered 1 x optical ).
You would get more stablitly if you raised the legs and dropped the center column of your tripod.
The use of Continuous Mode not only smoothes out any vibration from tripping the shutter but also enables you to capture the right angle of head turn so that the eye catches the light which is very difficult to anticipate ( and see) with one frame. Neil.
 
Hey Frank,
The Televue plossl recommended by Neil would certainly be a nice choice. Comparable to or better than the Siebert Performance 32mm.

Before I went with the Seibert line, I also thought long and hard and researched the Televues.

Here were the conclusions I came to for each of their eyepiece line:

1. Naglers (http://www.televue.com/engine/page.asp?ID=11) - Superwide FOV (in the 80's!) but they achieved it by shortening the eyerelief. This makes them great for eye viewing but poor choices for digiscoping. Also, their lowest mag eyepiece for the 1.25" barrel was 16mm. Their barrels in the lower magnifications which is best for digiscoping is also wider, probably too wide. Conclusion - pass. I wanted an eyepiece that was good for viewing and digiscoping.

2. Panoptics (http://www.televue.com/engine/page.asp?ID=24) - nice wide FOV's up to the 24mm. However, super massive barrels that is known to tip telescopes over. Uber pricey and eyerelief is too short for digiscoping. Conclusion - pass

3. Radians (http://www.televue.com/engine/page.asp?ID=23) - good eyerelief. Good sharpness. Price is more reasonable than Naglers and Panoptics. Reasonable size where a regular sized digiscoping adapter can fit. However, the Radian line only have FOV's of 60 degrees and the lowest power one is 18mm. Conclusion - can get wider FOV, lower powers, and same eyerelief elsewhere. Pass - but hesitantly

4. Plossl - Televue makes the best plossls. However, when I was buying eyepieces for my Pentax, I already had GTO plossls in the 40mm and 32mm so there was no point in buying another one. If you want to get them, they would be great choices in the 32mm and 40mm. Remember, I did recommend the 40mm plossl as the best, idiot proof digiscoping eyepiece around. However, like all plossls, the eyerelief falls below 20mm when the power exceeds 32mm. Also, the FOV is 50 degree at 32mm and 43 degree at 40mm due to the 1.25" barrel limitation (same applies to Sieberts) so one will have to live with the vignetting.

If you look at the high end eyepieces like Pentax and Televues, in the magnification range lower than 20mm (20mm to 40mm, especially the 20mm to 30mm range), there are very few choices for long eyerelief and wide FOV. That's why I am partial to Sieberts in this area. They fill out the weakness of the other high end eyepiece lines.

I got the Siebert 24mm Ultras because they provide the best balance of wide FOV, long eyerelief, and high light transmission/contrast at a barrel size I can loop a regular universal digiscoping adapter around.

Oh yes, please do spread those tripod legs out fully extended like Neil said and keep the center column as low as you can (even if you have to sit or hunch over or get on the knees, whatever). This could very well be the root cause of your less that optimal pictures. Check out the picture I took with both a Siebert 7mm Ultra and a Williams Optics 20mm when I had my center column extended to full height while the wind was blowing at the gun range (plus the legs on my tripod weren't fully spread out). I didn't post any of them up to this point because I was too embarrased :-O

I believe someone wrote somewhere on BirdForum that it is better to have cheap optics with a super stable tripod configuration than it is to have the best optics but a shaky tripod configuration.
 

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Neil,

Thank you for the information on the Plossls and the magnification range comparison. These may be what I am looking for.

Can Popper,

Great run-down on the various eyepieces. It is great to see more than just a description of each but an actual opinion of why each might be good for viewing or digiscoping.

In general, I am left with these thoughts. It seems obvious that a 32 mm Plossl or larger would be the smart choice in terms of a simple, foolproof digiscoping eyepiece. But, such an eyepiece would give me a magnification comparable to many of the binoculars I now possess, would it not? My little 65 mm scope has a much shorter focal length than the 80 mm models that most of you folks have. I would like to be able to digiscope at moderate distances (20-30 yards) as well as short distances. I am afraid that the Plossls in question would limit my ability to do that type of work.

The 28 mm Seibert Ultra sounds about right except the field of view is reduced to 60 degrees (as I would assume other manufacturer's eyepieces of this size would be as well unlness eye relief is compromised). Would the reduction in field of view cause excessive vignetting at no zoom on the camera? Would a moderate zoom 1.5x-2x on the camera then eliminate it?

With those thoughts in mind, maybe the 24 mm Seibert Ultra would be the route to follow though I am wondering whether or not that 4-5 mm size difference is enough to make a substantial contribution for increased light transmission.

Further thoughts on this issue would be much appreciated. Thank you folks.
 
Yup, it comes down to a choice between the 24mm and 28mm.

60 degrees is still fairly wide. The circle size should be between the pics of the Epic 2.3mm and the Ultra 24mm that I posted on the various eyepiece review.

Since you already have a 19mm and 20mm, why not give the 28mm a try to see how it works out? That would give you a bit more separation with what you have now.

We can even temporarily exchange our eyepieces, if you like. I have 2 Siebert Ultra 24mm's and my binoviewer isn't really working yet. I am curious to try out the Ultra 28mm myself but wifey isn't in the mood to spare me the budget :hi:


FrankD said:
Neil,

Thank you for the information on the Plossls and the magnification range comparison. These may be what I am looking for.

Can Popper,

Great run-down on the various eyepieces. It is great to see more than just a description of each but an actual opinion of why each might be good for viewing or digiscoping.

In general, I am left with these thoughts. It seems obvious that a 32 mm Plossl or larger would be the smart choice in terms of a simple, foolproof digiscoping eyepiece. But, such an eyepiece would give me a magnification comparable to many of the binoculars I now possess, would it not? My little 65 mm scope has a much shorter focal length than the 80 mm models that most of you folks have. I would like to be able to digiscope at moderate distances (20-30 yards) as well as short distances. I am afraid that the Plossls in question would limit my ability to do that type of work.

The 28 mm Seibert Ultra sounds about right except the field of view is reduced to 60 degrees (as I would assume other manufacturer's eyepieces of this size would be as well unlness eye relief is compromised). Would the reduction in field of view cause excessive vignetting at no zoom on the camera? Would a moderate zoom 1.5x-2x on the camera then eliminate it?

With those thoughts in mind, maybe the 24 mm Seibert Ultra would be the route to follow though I am wondering whether or not that 4-5 mm size difference is enough to make a substantial contribution for increased light transmission.

Further thoughts on this issue would be much appreciated. Thank you folks.
 
For further discussion on this issue here are some shots I took with three of my eyepieces. The first eyepiece is a Meade 25 mm that I have from a previous telescope. The second eyepiece is the Knight Owl EWA 20 mm and the third eyepiece is the Seibert 19 mm. Shots were of a mushroom at approximately 15 yards. It was quite dim and rainy today so shooting conditions weren't optimal.

I must say I was a bit surprised by the results. To the naked eye and through the camera display I could have sworn the Knight Owl looked the most pleasing but after uploading the pictures and running them through my imaging program the Seibert looks the best to me in terms of brightness and resolution. I do not have an explanation for it.

Edit: Excuse the blurred lettering. It did not come through as I had hoped. The camera settings were ISO 200, F 5.4, 1/100 and the pictures are in order from the Meade through the Knight Owl to the Seibert and reversed in the eyepiece comparison pic.

Can Popper,

We were both posting at the same time. My apologies. I think I may go the 28 mm route just for a change as you mentioned. We can see about exchanging possibly in the future. Thanks.
 

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Actually, the explanation is quite simple and straight forward.

You were taking the pictures on a dank rainy day when the light conditions were not so good. On those occasions, the Sieberts (in the 17mm to 19mm and 24mm) will out photograph all the other eyepieces because they use the fewest lenses to achieve a 20mm ER and wide FOV. Thus, the poorer the light, the better the Siebert will look.

My Siebert 24mm, which uses only 3 lenses to achieve 20mm ER and 65 degree FOV (versus 5-6+ lenses for all the others), also doubles up as my best low light eyepiece.

When lighting conditions are good, the difference between the Sieberts and others will be much less noticeable except at longer distances.


FrankD said:
For further discussion on this issue here are some shots I took with three of my eyepieces. The first eyepiece is a Meade 25 mm that I have from a previous telescope. The second eyepiece is the Knight Owl EWA 20 mm and the third eyepiece is the Seibert 19 mm. Shots were of a mushroom at approximately 15 yards. It was quite dim and rainy today so shooting conditions weren't optimal.

I must say I was a bit surprised by the results. To the naked eye and through the camera display I could have sworn the Knight Owl looked the most pleasing but after uploading the pictures and running them through my imaging program the Seibert looks the best to me in terms of brightness and resolution. I do not have an explanation for it.

Edit: Excuse the blurred lettering. It did not come through as I had hoped. The camera settings were ISO 200, F 5.4, 1/100 and the pictures are in order from the Meade through the Knight Owl to the Seibert and reversed in the eyepiece comparison pic.

Can Popper,

We were both posting at the same time. My apologies. I think I may go the 28 mm route just for a change as you mentioned. We can see about exchanging possibly in the future. Thanks.
 
Actually, the explanation is quite simple and straight forward.

You were taking the pictures on a dank rainy day when the light conditions were not so good. On those occasions, the Sieberts (in the 17mm to 19mm and 24mm) will out photograph all the other eyepieces because they use the fewest lenses to achieve a 20mm ER and wide FOV. Thus, the poorer the light, the better the Siebert will look.

That would make sense except, as I mentioned, the Knight Owl actually looked the best before I put it into the imaging program. I wonder why the difference between my own eyes and the image eventually on the computer. All images were spliced together before I did any enhancement.
 
That could probably be due to the way the EWA brings the image together. I believe the ER on the EWA 20mm is 17mm while the Siebert is 20mm. So given the larger ocular lens of the EWA and faster converging light path, the EWA has a fatter light cone.

Given the ways your eyes are shaped, the fatter light cone may agree with your eyes more.


FrankD said:
That would make sense except, as I mentioned, the Knight Owl actually looked the best before I put it into the imaging program. I wonder why the difference between my own eyes and the image eventually on the computer. All images were spliced together before I did any enhancement.
 
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That could probably be due to the way the EWA brings the image together. I believe the ER on the EWA 20mm is 17mm while the Siebert is 20mm.

Hmm, it is funny you say that because I would have guessed just the opposite dimensions.
 
Well, those are the paper specs. *grin* Like my Pentax SMC zoom has paper specs of 20mm ER but it sure doesn't feel like it; it feels more like it has ER of 13mm.

Only way to know conclusively is to take a flashlight and shine it into the scope side of the eyepiece. Point the ocular side of the eyepiece against the wall and move it in and out until it brings the light to a sharp focus. The distance between the eyepiece (the way you measure it; I suspect some manufacturers measure ER from the center of the eye lens as opposed to the edge of the eyepiece) and the sharp focused image is the eyerelief.
 
Thanks CP. If I get a chance later I may try that out.

Just out of curiousity, are there any inexpensive eyeypieces offered in the range we are talking about from other manufacturers? I was thinking of going back to Owl Services to take a look at what else they have in stock or maybe those Epic ED IIs I saw mentioned in another thread? I know field of view might be a bit tighter but with the 1.5-2x zoom on the digital camera I should still be alright. I might still buy the Seibert but would like to see if there is a less expensive option first. Money just got alot tighter. ;)
 
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The air gets pretty thin in the 20mm to 30mm range, unfortunately. Most manufacturers don't really bother with this range probably because many telescopes come with a cheap 24mm or 25mm eyepiece thrown in.

From my search, the cheap eyepieces all come with some wart.

There are only 2 cheaper eyepieces in the 20mm to 30mm range that works well with the fast F ratio of the Pentax and have mostly to the edge clarity and meets the 20mm ER requirement.

They are:
1. Edmund Scientific RKE 28mm - you can find a review (#9) of it here towards the middle-lower section http://www.schellweb.org/html/eyepieces.html. Edmunds also have a section on eyepieces here: http://www.edmundoptics.com/techSupport/DisplayArticle.cfm?articleid=271 This should work super well with digiscoping if you don't mind doing some cropping of the images due to its relatively narrow 45 degree FOV. You can order them here for about $55 http://www.edmundoptics.com/onlinecatalog/DisplayProduct.cfm?productid=2075

2. Orion Epic ED-2 - uses 6 lenses so it will work with the fast speed of the Pentax. 55 degree FOV and it goes down to the 25mm. Here is a discussion thread I found on it: http://astronomy.com/ASY/CS/forums/290895/ShowPost.aspx Kind of mixed but it looks like the camera may like it better than the eyes. Here is a cloudy nights review: http://www.cloudynights.com/item.php?item_id=259

Other eyepieces unfortunately don't work well with the fast speeds of the Pentax in the 20mm to 30mm range.

FrankD said:
Thanks CP. If I get a chance later I may try that out.

Just out of curiousity, are there any inexpensive eyeypieces offered in the range we are talking about from other manufacturers? I was thinking of going back to Owl Services to take a look at what else they have in stock or maybe those Epic ED IIs I saw mentioned in another thread? I know field of view might be a bit tighter but with the 1.5-2x zoom on the digital camera I should still be alright. I might still buy the Seibert but would like to see if there is a less expensive option first. Money just got alot tighter. ;)
 
Can Popper,

Thank you for the suggestions. The Epic ED2 has me intrigued with the low dispersion glass and relatively favorable reviews. However, I spent some time this evening using the 19 mm Siebert out in the backyard. My expectations weren't high because of the fairly average performance it gave the other day but I wanted to give it another go.

I posted some of the pics over in the digiscoping main forum and in the digiscoping camera forum under my Image Quality Help and Casio Exilim threads respectively. The results were very favorable in my opinion. Resolution was probably the best yet as was the amount of the image in focus. This seems to be one of those cases where the camera likes the eyepiece better than my eye as I still tend to favor the EWA 20 mm. The entire viewing experience of the EWA seems more relaxed and comfortable to me...seems like a wider field of view, more detailed image, etc... If you haven't picked up one of the EWA's yet then I would definitely suggest giving the 20 mm a try. Speaking of which I decided to do another comparison picture between the 20 mm EWA and the 19 mm Siebert. This time the results were just the opposite in that the EWA produced the brighter image. Resolution appears about equal to my eyes but I will leave the comparison up to you folks. Also included are a few pics with the Siebert 19 mm. Camera settings were ISO 100 F4.8 1/10 for the dove pics and ISO 400, F2.8 1/80 for the direct picture comparison. The Siebert is the first hummingbird feeder pic and the EWA the second. I am thinking about taking the scope outside this evening to snap a few pics of some celestial bodies. ;)
 

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