• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

SW80 ED, Basic Questions (1 Viewer)

Polaroid

Member
After reading this Astro forum for weeks and finally ordering an sw80 ed, I finally joined and brought my beginner questions. I ordered the often referenced telescope and added a one piece extension with male t thread. I have a female t thread Nikon adaptor. I now ponder these questions. Will the telescope objective cover a prime focus full frame (35mm) sensor without significant vignetting? Will the Crayford style focuser hold a full size SLR camera without slipping. Should a Vixen Pronto II head function well for imaging waterfowl? Will I immediately find a need for an increase in magnification?

I really appreciate all I have gained from reading in this forum.
 
After reading this Astro forum for weeks and finally ordering an sw80 ed, I finally joined and brought my beginner questions. I ordered the often referenced telescope and added a one piece extension with male t thread. I have a female t thread Nikon adaptor. I now ponder these questions. Will the telescope objective cover a prime focus full frame (35mm) sensor without significant vignetting? Will the Crayford style focuser hold a full size SLR camera without slipping. Should a Vixen Pronto II head function well for imaging waterfowl? Will I immediately find a need for an increase in magnification?

I really appreciate all I have gained from reading in this forum.
Hi
I guess you are using a Nikon FF camera? Which one?
Most people here either use cropped APS sensors, or m4/3, and vignetting is not visible on these smaller sensors.
The sensor diagonal is about 43 mm and the extension tube diameter about 51mm (2") so you may notice a slight vignetting on a FF sensor. A friend once borrowed my TS102 scope for use with his Nikon D800 and did not complain about significant vignetting. I also notice you do not mention ordering an extension tube, which is an essential accessory to be able to focus at useful distances.
The Crayford focuser can be tightened or loosened using the hex screw on the bottom, an easy operation. It tends to become loose with time and operation. Just tighten it so the focuser does not slip when pointing up/down, not too tight. You mention waterfowl, I guess the shooting angle will be more or less level. Regarding need for magnification - you will get the same angle of view/reach as a 600mm telephoto lens.
 
You will get vignetting with a FF sensor on the Skywatcher. You have to use a 3" Focuser to avoid vignetting, maybe a bit less with a 2 1/2", but the standard 2" will be very noticeable. I don't think you can change the focuser with the SW80ED.
 
You will get vignetting with a FF sensor on the Skywatcher. You have to use a 3" Focuser to avoid vignetting, maybe a bit less with a 2 1/2", but the standard 2" will be very noticeable. I don't think you can change the focuser with the SW80ED.
True, Dan. It occurred to me my TS102 is fitted with a 3" focuser first after I read your post. My friend also tested my TLAPO804 (fitted with with 2" focuser) and now I remember he mentioned vignetting was noticeable on his D800.
 
Using a field flattener should give a big enough image circle for full frame, something in the order of a 44mm image circle or bigger should be possible. You may have to take small reduction in magnification though.

Using a low power teleconverter with a macro tube between it and the camera would project a bigger image circle too.

Paul.
 
Welcome to the club. The SW80ED is a fine scope at a very good price enjoyed by many of us. I wish you fun and success with it.

I cannot comment on vignetting since I use a M43 camera but here is a bit of info on the focuser. When properly adjusted, it works beautifully: it is smooth and does not slip at all. The 2 button focuser is even better, allowing very precise adjustments.

It is quite easy to take down but you need to be careful not to loose the small o-rings. Is is also easy to reverse the knobs to have the dual knobs on the left so that you can control the camera with your right hand while focusing with the left hand.

See these articles:

http://www.teleskop-austria.at/info.../pdf/Crayford_adjustment_Synta_microfoc-1.pdf

You will have to register to see all threads to this fine article, the best I have found. Registration is free.
http://www.astronomyshed.co.uk/foru...4418&hilit=focuser+adjustment+solution#p34418

Instructions on switching the knob - post #366
http://www.birdforum.net/showthread.php?t=194800&page=15

I also posted instructions in this forum on adjusting the focuser but I can't find it. There seems to be a problem with the search function. The 3 URLs above should give you all the info you need.

I also think you should consider flocking the inside of the focusing part of the scope (adapters, extension and focuser tube). It will substantially improve contrast and does not cost much.

Good luck
Jules
 
Thank you all. I have a D800 which has enough pixels to allow for a bit of cropping. I was optimistic regarding coverage but visually, the set-up with a 2" extension was suggesting a coverage issue. Thank you for the assurance that the focuser should serve me. I did order a combined extension and t adaptor. Yesterday I discovered my camera has a mirror lock-up with 3 second exposure delay. Wow. That could solve a big concern regarding mirror flip motion. Again, thank you all and I look forward to getting the kit and putting it all together and awaiting the bird.
 
Todd, My grandparents, all but one, were Swedes. The one was Norwegian. Overhearing conversations, the mix was not commonly well received. Regardless, I saw the listings for the TS102 and it appeared as a fine instrument.
 
Thank you all. I have a D800 which has enough pixels to allow for a bit of cropping. I was optimistic regarding coverage but visually, the set-up with a 2" extension was suggesting a coverage issue. Thank you for the assurance that the focuser should serve me. I did order a combined extension and t adaptor. Yesterday I discovered my camera has a mirror lock-up with 3 second exposure delay. Wow. That could solve a big concern regarding mirror flip motion. Again, thank you all and I look forward to getting the kit and putting it all together and awaiting the bird.

I would'nt worry about mirror slap. Just set ISO high enough to keep your shutter at about 1/1000s or more. If light is not good, your photos will lack contrast and the results won't be great, mirror lock-up or not.

You will have to do your classes to learn how to work with the scope. You need to keep the camera stable, press the shutter smoothly and focus quickly while the bird is still there. Expect so-so results at first but your photos will quickly get better.

Put the camera in A mode, manual focus and use a high enough ISO. Then forget about camera settings and concentrate on fucusing. If possible, pre-focus for the expected distance. Keep the camera as low as possible on the tripod and avoid using the tripod extension tube.

Enjoy
J
 
Thank you J. I was skilled with slow shutter speeds (1/15th, normal lens) shooting a rangefinder Leica but have not been able to duplicate the results with a full frame SLR. I use the exhale hold and squeeze technique. I will probably stick to full sun for contrast. Yes, A mode is common practice as is Manuel Focus. I'm an old head photographer and enjoy having image control. Now that I'm retired, I hopefully have the patience for imaging birds.
 
I myself wouldn't worry about it. Just shoot and use the center part of the frame. Later you can move up to something more expensive with a larger focuser, but there won't be a huge difference in the center sharpness. The SW 80 ED is a lot of bang for the buck.
 
Thank you J. I was skilled with slow shutter speeds (1/15th, normal lens) shooting a rangefinder Leica but have not been able to duplicate the results with a full frame SLR. I use the exhale hold and squeeze technique. I will probably stick to full sun for contrast. Yes, A mode is common practice as is Manuel Focus. I'm an old head photographer and enjoy having image control. Now that I'm retired, I hopefully have the patience for imaging birds.

In the past on my SW80ED I could get sharp photos down to around 1/25 without mirror slap being a problem and I'd use the same exhale technique. Sometimes I'd hold my breath too long and my heartbeat would be a visible vibration in the viewfinder. I'd have to time the photos between heartbeats. The main problem at speeds that low are that the bird is rarely still enough. On my Nikon D3300 that I have now I can put the ISO up so high without noise being a problem that low shutter speeds are no longer an issue.

Paul.
 
A 700mm focal length sounds like a lot of reach to me. I never used more than a 200mm telephoto. Is a 1.4 teleconverter useful? I see much reference to them being used. Arn't atmospheric conditions significant, such as haze and heat refraction waves, thereby making additional magnification a much greater challenge? Stability, of course, becomes more significant. If a teleconverter is, in fact, a practical tool, which one would be suggested for use with a Nikon D3300 or d800?
 
A 700mm focal length sounds like a lot of reach to me. I never used more than a 200mm telephoto. Is a 1.4 teleconverter useful? I see much reference to them being used. Arn't atmospheric conditions significant, such as haze and heat refraction waves, thereby making additional magnification a much greater challenge? Stability, of course, becomes more significant. If a teleconverter is, in fact, a practical tool, which one would be suggested for use with a Nikon D3300 or d800?
The ED80 scope has a 600mm focal length. It gives quite a lot of reach, and is just about right in many situations. Adding a TC should not be necessary to start with. It adds to the challenge (850mm, F/11 something).
 
I think 1.4X is a very useful size to use, it's probably what I use 90% of the time if conditions allow it. Most of my photography is done in winter and spring though. Try cropping first and if that's no good then start with a low power TC. Cropping a 1.4X usually gives better results than using a 2X TC for example. If you are ok with some diy then the homemade ones mounted in the extension tube work as good as a Kenko Pro for example.

Paul.
 
Last edited:
My error Tord, 600mm is correct. I will work with what I get when the telescope finally arrives. I do have another question. This one is probably best for Paul. Do I need to enter menu settings for a non chip lens? If so what is best?
 
My advise is to start using the scope without TC and take it from there. The main challenge is focusing accurately, at 600mm the depth of field is shallow. To get perfect focus you may want to examine using Live View in magnified mode. This is what I sometimes did when using mirror DSLR, but often the action is too fast to allow for that.

Regarding camera settings - what did you have in mind? Regard the scope as a telephoto lens with MF and fixed aperture. I would shoot in AV (sometimes M) and adjust ISO high enough to get acceptable shutter times. How short depends on conditions and your skills in mitigating shake blur. Maybe also delay shutter to mitigate vibrations from mirror slap. Paul with experience from Nikon is the right guy to answer I guess.
 
I do have another question. This one is probably best for Paul. Do I need to enter menu settings for a non chip lens? If so what is best?

If you have that option then you can set the focal length to 600mm and f7.5 aperture. There's no option to set lens data on my D3300. So what I have done is to buy a dandelion CPU chip and glue it into the scope adapter that mounts to the camera. Then you can program the chip with all the data that you are likely to use. I've programmed mine for the scope at 600mm/f7.5 and also for a couple of my teleconverters and it works very well. I get proper light metering and it allows me to use other modes apart from manual.

Paul.
 
Warning! This thread is more than 9 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Users who are viewing this thread

Back
Top