Astro telescope for Olympus 4/3? (1 Viewer)

Hi,

I started digiscoping the past winter, using Nikon spotting scope with S95 compact camera and later on also using the scope as a lens for my DSLR.

I have achieved results I am quite pleased with and based on this I am considering taking next steps to with the ambition to get even higher image quality at long range. The photos on display in this section of the forum are really inspiring and I would like to better understand astro/telescope setups, what setups are proven to work and what is needed to get started.

Questions on high level from the top of my head:

• There seems to be a multitude of telescopes with different designs. What designs are recommended to be used as super telephoto lenses on DSLR?
• What make should I look at? Names I seen mentioned here are Celestron, Sky-watcher...
• What adapter do I need to attach my DSLR to the scope, and to get a useful angle of view? Or am I wrong in my understanding, should I use a compact camera instead?
• Are there any other accessories strongly recommended to get a useful setup?
• What kind of tripod head is recommended? (I suppose it depends on the scope design).

Application area: bird photography, long range shooting, reasonable portability.

Apologies for bothering with questions that have probably been asked and answered many times.

Lastly perhaps I should mention my DSLR gear is Olympus 4/3, and since I live in Sweden I would like to be able to source from European retailers if possible (to avoid addtional VAT and customs).


Best Regards
Tord

If you've read the Astro gear that Paul C , Fernando Batista, Cango, Alphan and others are using, then you already know what gives
good results

The names of their scopes are all in most of their posts. You wont go far wrong with using one of those scopes. Just need a T mount adapter for scope to camera mounting, and the appropriate length of ext. tubing. And a tripod/monopod

Hej!

I'm too an olympus user (E-3) and have a celestron 80ed. look at the thread http://www.birdforum.net/showthread.php?t=194800 for the different setups.

I'm not qualified to answer regarding long range use of the scope, but take a look at the thread regarding barlows/teleconverters
http://www.birdforum.net/showthread.php?t=182146
where there is good info. (I prefer to shoot whithin 15 meters max. smaller birds, that is. for bigger, of course it can be extended)

Tord,

If I am to start all over again, my setup would be:
1) scope, either Celestron 80ED, Skywatcher ED80 or Orion 80ED depending on where you get it from. These are the best value for your money and all three have the same glass and same manufacturer.
2) a T2-M42 adapter
3) a set or two of M42 macro extension tube
4) an M42 to camera mount adapter (in your case M42- 4/3 adapter)

This revised setup all comes screwed in except the 4/3 mount to your camera. All mounts (except M42 screw) cause some slag and with the length of extension and weight of camera, the slag can be quite high.

As for tripod head, the Gimbal or Manfrotto 393 would be nice. The normal video head (3 way head) are fine too. Just make sure they are HD enough to support your combined setup. I do not recommend Ball head as it not only tilt up and down, swing left and right. It also tilt sideways making it another movement harder to control. With the above mentioned head, you can shoot speedily like firing a machine gun. The Gimbal or Manfrotto head when balanced will return your scope to floating position without the need to lock while waiting for birds.

As to where to buy them, you have to search the web to suite your location. I would not be overly bother with TCs and the above scope will give you 1200mm after crop factor. The TCs and focal reducer can comes in when you got used to your system and only yourself can determine what else you need. A common mentality with birding is the longer the better but that doesn't hold true. There had been many missed golden opportunities when I had and 2X TC installed only to find the bird too big to fill the frame, the longer time needed to get the target in view, and worst of all, atmospheric distortion blurring out the image. I once experience a bird barely 120m away but the atmospheric distortion produced a picture like taken with a kit lens with some 2 or 3 TCs stacked.

Hope this helps.

Dear Tord,

It is also to note that attachinga DSLR directly to some astro scopes will result in inverted images, if you don't attach the DSLR to an image inverter beforehand. The eyepiece of the astro scope has an inverting prism that allows you to view the image therein the right way up. Your Nikon Scope Adapter also does this function for you.

Also bear in mind that using catadioptic (or relector or mirror) scopes will subject you to the same limittions as catadioptic lenses.

Good luck in your experimenting!

Hor Kee

Hor Kee said:

Dear Tord,

It is also to note that attachinga DSLR directly to some astro scopes will result in inverted images, if you don't attach the DSLR to an image inverter beforehand. The eyepiece of the astro scope has an inverting prism that allows you to view the image therein the right way up. Your Nikon Scope Adapter also does this function for you.


Hor Kee

Click to expand...

This is wrong information Hor Kee.

Attaching a dslr directly to an astro scope will not ever result in an inverted image.

Eyepieces do not have an inverting or correcting prism inside them, they just invert the image due to the arrangement of the optics. I think you are getting confused with spotting scopes that have a prism inside the scopes body. All the info you have given is referring to a spotting scope setup.

Paul.

Hej,

Thanks a lot for the replies, highly appreciated.

I will study what you write and look at the setups in details.

Am I right in that TC = Teleconverter? And may I ask what a "focal reducer" is and what purpose it serves?

I also understand I should look at refractor scopes, not reflector scopes, to avoid the unpleasant "donuts". The scopes mentioned in the replies seem to be refractor scopes.

Cheers
Tord

Tord.

Telescope Service are in Europe and quite good value I think. Their website is here.

http://www.teleskop-express.de/shop/index.php/language/en

You are correct, TC is teleconverter. A focal reducer will shorten the focal length of the telescope. My reducer takes the scope from 600mm down to 360mm. This is good for close up stuff at say 3m or 4m range. It also gives you faster shutter speeds because the f ratio is reduced. The SW80ED is f7.5 but my focal reducer takes it to f4.5

Paul.

Hej Cango,
I studied your setup and have a couple of questions. Sorry for bothering...

/Tord

cango said:

Hej!

I'm too an olympus user (E-3) and have a celestron 80ed. look at the thread http://www.birdforum.net/showthread.php?t=194800 for the different setups.

Click to expand...

• You write "Indian" gimbal tripod head: do you mean from Induro? Is it the GHB1?
• Are the Induro heads compatible with a Manfrotto tripod? (I use a Manfrotto 055 and 128RC head for my scope).
• Regarding the "2" UltraWide Prime Focus Telescope Adapter", I I get it right you use an adapter for OM and a OM legacy lens - 4/3 digital body adapter ring. Any particular reason for doing so since there also exists an adapter that directly fits 4/3 digital?

I'm not qualified to answer regarding long range use of the scope, but take a look at the thread regarding barlows/teleconverters
http://www.birdforum.net/showthread.php?t=182146
where there is good info. (I prefer to shoot whithin 15 meters max. smaller birds, that is. for bigger, of course it can be extended)

Click to expand...

What I am looking for is a setup that provides a focal length of clearly above 500 mm (true FL, not "35 mm equivalent") and with reasonable portability and ergonomics. My Nikon ED82A/DLSR setup exceeds this spec by far and can produce good results at distances exceeding 25 meters but the ergonomy is not fantastic due to the angled scope making it sometimes difficult to frame the subject and also due to dark viewfinder making pin sharp focusing a challenge. The spec for the setup (picture attached) is 1200 mm at F/12.8

Suppose I already have Olympus teleconverters (EC14 and/or EC20), would those be suitable for use with your setup? And what is the F-number for your setup by the way?

Setup attached.

You write "Indian" gimbal tripod head: do you mean from Induro? Is it the GHB1?

Mini Gimbal fron a dealer in India.
http://cgi.ebay.com/Mini-Gimbal-Hea...247?pt=LH_DefaultDomain_0&hash=item20b4eec0af

Are the Induro heads compatible with a Manfrotto tripod? (I use a Manfrotto 055 and 128RC head for my scope).

No idea.


Regarding the "2" UltraWide Prime Focus Telescope Adapter", I I get it right you use an adapter for OM and a OM legacy lens - 4/3 digital body adapter ring. Any particular reason for doing so since there also exists an adapter that directly fits 4/3 digital?

Yes, my reason for doing so is to be able to have a AF-confirmation chip in the OM-to-fourthirds-adapter (a regual adapter that lets you put old Olympus OM lenses on the digital system.)

You could of course not use a AF-confirmation chip, but it helps manual focus.
Of course, it all depends on how good your eyes are, and how bright your viewfinder is. You could buy the chip alone and glue it onto the 2" telescope adapter with 4/3 mount -(I tried with no luck, so I opted for the adapter with the AF-chip already on it - leaving me no other option than to get the 2" telescope adapter with OM mount. Hope it makes sense)



Suppose I already have Olympus teleconverters (EC14 and/or EC20), would those be suitable for use with your setup? And what is the F-number for your setup by the way?

Yes those would work - put them closest to the camera and then the rest.

The scope I have Celestron 80ED (same as the other 80Ed) all are F7.5.
I rarely use converters (have only an old OM-tc) so I shoot at 600mm (true FL) 99.5% of the time.

Cango,

Thanks a lot for explanatory answers.

Btw I had a look at your web site and must say the photographs are really good.

/Tord

Tord said:

Cango,

Thanks a lot for explanatory answers.

Btw I had a look at your web site and must say the photographs are really good.

/Tord

Click to expand...

Tackar så hemskt mycket!

Feel free to ask as much as you like. This forum is great.

cango said:

Tackar så hemskt mycket!

Feel free to ask as much as you like. This forum is great.

Click to expand...

Hi Cango,

I have a question. The "indian Mini Gimbal Head" comes with one free plate. Either of PT-10, PT-20, PT-30, PT-40, PT-50 if I understand correctly.

There is some not so clear/contradictory information regarding what plate to pick. The general guideline stated by the vendor is: "The PT-10 can be used with upto 100mm Telephoto lenses, PT-20 with upto 200mm lenses and so on....." but this guideline seems not valid looking at what plates are recommended for specific lenses (scroll down to the end of page to see what I mean).

(It could also be that the mm used in the guideline refer to the actual length of the lens, not the focal length. Hmm... )

Hence I have a few questions to you:

• What plate did you select for the Celestron ED80?
• What would you select to work with the Zuiko 50-200 SWD? (this is the lens I usually use)

Cheers
Tord

I made my own plate - 200mm (could have done it 2-4cm more).

As you see in the picture, I must have the plate on the side, not underneath, the scope. Ideally, I would have fixated the plate directly onto the scope tubing, but now I decided to use the celestron clamps (the black you see inte middle of the scope. These are about 500 grams, so eventually I will get rid of them, to loose the weight, but haven't got the time to fix me a new plate.)

Why such a long plate? Well, the gimbal, as you might know, works with balance. And with common telelenses with internal focusing balance seldom changes. The way we reach focus on a scope changes the balance, therefore I have to loosen the plate/scope from the gimbal and move it back or forth to reach balance again. A long plate helps here. And when you use the scope as a spotting scope - the balance changes very much, and long plate is of help again.

to the 50-200mm I'll go with 5-6-7cm.

Thanks,

I follow you regarding the balance issue and the need for a plate that matches the gravity center of the setup.

Bits and pieces are slowly coming into place as I try to understand this partially new world. Still, there are several areas that are confusing to me.

You mention the need to use a macro extension tube with recommended length 80 mm.
==> Is this a device with the same functionality as a regular extender used for macro photography? Is the purpose to allow to position the lens in relation to the body so that the focal plane is on the camera sensor?
==> Is the 80mm length critical? I mean, in next step you attach it to the DSLR using the "" UltraWide Prime Focus Telescope Adapter", which in turn adds length... hence the question if the length is critical.
==> Is the device generic in the sense that it will fit several scope makes, or is it specific for different makes? The scope retailers don't list such a device among scope accessories, only eyepieces, so I get confused

BTW it seems the Celestron refractor 80ED lens has been discontinued... which means I should probably look at other sources (Orion and Sky-watcher have been mentioned by others as makes to have a look at).

/Tord

Tord said:

Hi Cango,

I have a question. The "indian Mini Gimbal Head" comes with one free plate. Either of PT-10, PT-20, PT-30, PT-40, PT-50 if I understand correctly.

There is some not so clear/contradictory information regarding what plate to pick. The general guideline stated by the vendor is: "The PT-10 can be used with upto 100mm Telephoto lenses, PT-20 with upto 200mm lenses and so on....." but this guideline seems not valid looking at what plates are recommended for specific lenses (scroll down to the end of page to see what I mean).

(It could also be that the mm used in the guideline refer to the actual length of the lens, not the focal length. Hmm... )

Hence I have a few questions to you:

• What plate did you select for the Celestron ED80?
• What would you select to work with the Zuiko 50-200 SWD? (this is the lens I usually use)

Cheers
Tord

Click to expand...

Dear Tord,

You may want to buy a longer plate as your setup's pivot point (i.e. the tripod shoe of your scope) is located in a forward position relative to your setup's center of gravity. This means that the part of your setup where your Olympus DSLR is attached to is heavier than the front of the scope. A longer tripod plate will help you shift the center of gravity backwards for a more balanced setup. In my opinion, the PT-30 plate may be long enough to accommodate your setup and balance it evenly.

By contrast, my setup using an older ED78 scope as discussed earlier here http://www.birdforum.net/showthread.php?p=2162623#post2162623 has its tripod shoe located much further back. Therefore, the pivot point of my setup is closer to the setup's center of gravity. As such, I only need a short tripod plate. When attached to my gimbal head, the location of my setup's tripod shoe is not very far off the center of the gimbal plate holder.

By contrast, your setup will have the gimbal head grasping the rear end of the tripod plate while your scope is attached to the front end of the same tripod plate. This should bring your setup's center of gravity backward to achieve balance. Do make sure that your gimbal head's tripod shoe clamp is sufficiently strong for this purpose.

Hope this helps!

Regards,

Hor Kee

You mention the need to use a macro extension tube with recommended length 80 mm.
==> Is this a device with the same functionality as a regular extender used for macro photography? Is the purpose to allow to position the lens in relation to the body so that the focal plane is on the camera sensor?

Not sure what the minimum lenght would be, but 50mm extension tube works (that I have tried). I'm not qualified to answer if it's the same thing you are referring to - but the extension tub puts the camera away from the lens making it able to reach (near) focus. With 50mm tube, the nearest I can have a bird and focus on it perhaps is around 10-12 meters - and I can get focus at infinity as well. BUT, with 80mm I can reach near focus much closer (7-9 meters) However I loose infinity focus. The farthest I may be able to focus might be 100 meters. (which for me, it doesn't matter for photography, since heat and shake will have ruined the photo anyway. But I lack not being able to at least tell what kind of bird that I thought I saw at that distance.)

So, it really depends on what kind of shooting you expect to do.

=> Is the 80mm length critical? I mean, in next step you attach it to the DSLR using the "" UltraWide Prime Focus Telescope Adapter", which in turn adds length... hence the question if the length is critical.

No it's not critical - the 80mm lenght (see above answer) but you'll have to have some extension. And no, the prime focus scope adapter does not really add lenght, since it's stuck within the extension tube. (see my pictures) BUT - you can pull out the prime f. adapter a centimeter or so (tightening the screw anew) in situations when you want closer near focus. Be careful not to forget to fasten the screw or you drop the camera.
==> Is the device generic in the sense that it will fit several scope makes, or is it specific for different makes? The scope retailers don't list such a device among scope accessories, only eyepieces, so I get confused

BTW it seems the Celestron refractor 80ED lens has been discontinued... which means I should probably look at other sources (Orion and Sky-watcher have been mentioned by others as makes to have a look at).

Yes. In terms of weight, I found it to be the lightest of them then available to me scopes. (and cheapest). Just a week ago, I was helping another person from Sweden these same scope questions (a photographer wanting more reach, for a good price) and I found this celestron scope at ebay, but now gone.

Hor Kee said:

Dear Tord,

You may want to buy a longer plate as your setup's pivot point (i.e. the tripod shoe of your scope) is located in a forward position relative to your setup's center of gravity. This means that the part of your setup where your Olympus DSLR is attached to is heavier than the front of the scope. A longer tripod plate will help you shift the center of gravity backwards for a more balanced setup. In my opinion, the PT-30 plate may be long enough to accommodate your setup and balance it evenly.

By contrast, my setup using an older ED78 scope as discussed earlier here http://www.birdforum.net/showthread.php?p=2162623#post2162623 has its tripod shoe located much further back. Therefore, the pivot point of my setup is closer to the setup's center of gravity. As such, I only need a short tripod plate. When attached to my gimbal head, the location of my setup's tripod shoe is not very far off the center of the gimbal plate holder.

By contrast, your setup will have the gimbal head grasping the rear end of the tripod plate while your scope is attached to the front end of the same tripod plate. This should bring your setup's center of gravity backward to achieve balance. Do make sure that your gimbal head's tripod shoe clamp is sufficiently strong for this purpose.

Hope this helps!

Regards,

Hor Kee

Click to expand...

Dear Hor Kee,

Thanks, it makes sense and helps in getting the picture.

I understand I will need a plate that is at least long enough to match the distance between the socket on the scope and the centre of gravity. And I also realize there is a limit for what torque can be excercised on the tripod head and its clamp without risking premature fatigue/risk of damage/failure.

I also guess the plate would benefit from being extended to provide additional support to the camera body, avoiding stress and avoid risking the camera bend downwards due to the weight of the adapter/extension tube/camera. I suppose I will need to handcraft such an extender out of e.g. an aluminium profile.

/Tord

cango said:

Not sure what the minimum lenght would be, but 50mm extension tube works (that I have tried). I'm not qualified to answer if it's the same thing you are referring to - but the extension tub puts the camera away from the lens making it able to reach (near) focus. With 50mm tube, the nearest I can have a bird and focus on it perhaps is around 10-12 meters - and I can get focus at infinity as well. BUT, with 80mm I can reach near focus much closer (7-9 meters) However I loose infinity focus. The farthest I may be able to focus might be 100 meters. (which for me, it doesn't matter for photography, since heat and shake will have ruined the photo anyway. But I lack not being able to at least tell what kind of bird that I thought I saw at that distance.)

So, it really depends on what kind of shooting you expect to do.

Click to expand...

I understand (I do some macro photography, sometimes with extension tube). I suppose I will need to customize the astro lens setup for good fit with the 50-200 lens that I usually have readiliy available mounted on another body.


By the way, may I ask again if the extension tube is generic in the sense that it will fit several scope makes, or is it specific for different makes? The scope retailers don't list extension tube among scope accessories.

/Tord