DSLR lenses on ZWO cameras

[Misterfied]

 I am looking to fit a DSLR lens onto a zwo camera and the actual fitting together to achieve focus is no problem.....but my question is.... what is the best zwo camera to buy ( with regards to sensor size ) because the image circle from the DSLR lens would overlap most of the sensors on the zwo cameras? Or do I need to buy a zwo with full frame sensor???? Ps ...I already own zwo 1600 on my telescope. But never tried it with DSLR lens because of small sensor.... and it’s mono..... looking to put together a portable imaging rig..... skywatcher Star Adventurer... polemaster.... zwo colour camera... DSLR lens... any info would be good.. Thanks in advance

 

 

[Demonperformer]

Hi, Mistified, and welcome to SGL.

I have used a 1600 with my canon lenses and produced reasonable results. I recently swapped my 1600 mono for a pair of 183s, but haven't used the lenses with them. I would start out using the 1600 and see how things go. You can always change the camera if it is not giving you the results you want ... and you will at least know what is wrong with the results you have got with the 1600 and so know what you are trying to achieve with the change. I have found this concept to be the most helpful thing when I am wondering what I should buy ... once I know what I am trying to achieve by the change, I tend to make much better buying decisions.

There are two zwo adapters, and one will allow a filter wheel to be fitted in the optical train. The cost of the filter wheel and filters (if you don't already have them) might be more cost efficient than buying a whole new camera ...

[Misterfied]

Yes I already have a filter wheel with 1600 mono cooled on a 100 mm f5 scope for deep sky wide field and love it.... I’m more after a setup for really wide nightscape/ Milky Way with foreground ... that’s why the question about sensor size.... I’m not sure how it will work with DSLR image circle on such a small sensor.... I guess I should just test it without the filter wheel

[Demonperformer]

Of course, it depends on exactly what length lens you are using, but with a standard 50mm, the 1600 has a fov of 20x15 degrees.

[Knight of Clear Skies]

The field of view with the 1600MM Cool is a bit smaller than a DSLR due to the smaller sensor, here's two images with a 135mm lens that shows the difference:

(~20 minutes @ f2,  7nm Ha filter, 1600MM Cool)

(22 minutes @ f2, 12nm Ha filter, 1100D)

Edited April 25, 2019 by Knight of Clear Skies

[Knight of Clear Skies]

Just to add, there are pros and cons to using camera lenses with smaller sensors. While much of the image circle is wasted lens aberrations and vignetting are less noticeable because the corners are cut off, sometimes the lens needs to be stopped down half a stop less which produces a brighter image. Also, depending on the target, the smaller field of view may not be important.

The 1600MM Cool, with its small pixels, is a good match for lenses in the 135mm-200mm range. Even 135mm is enough to resolve good detail on many DSOs, note the dust pillar on the head of the Pelican in the image above.

[alan potts]

This is something I what to try as I have a few very nice Canon L lenses, the trouble I have is mounting them with only a 5kg counter weight, still the 500mm F 4 should be OK, maybe small lenses just won't trouble the mount too much (azeq 6).

[Knight of Clear Skies]

3 hours ago, alan potts said:

...the trouble I have is mounting them with only a 5kg counter weight...

To improvise a lightweight counterweight you could try putting something in a sock and attaching it with rubber bands.

[Stub Mandrel]

On 25/04/2019 at 06:20, Misterfied said:

Yes I already have a filter wheel with 1600 mono cooled on a 100 mm f5 scope for deep sky wide field and love it.... I’m more after a setup for really wide nightscape/ Milky Way with foreground ... that’s why the question about sensor size.... I’m not sure how it will work with DSLR image circle on such a small sensor.... I guess I should just test it without the filter wheel

Having a small sensor will never cause problems, it just means you won't enjoy as wide a field of view with the 1600 as with an APSC/Full Frame sensor.

The filter wheel should not be an issue either.

Try setting up your system options in Stellarium or a similar program to see what sort of image scale you get.

[Andywilliams]

On ‎25‎/‎04‎/‎2019 at 19:43, Knight of Clear Skies said:

Just to add, there are pros and cons to using camera lenses with smaller sensors. While much of the image circle is wasted lens aberrations and vignetting are less noticeable because the corners are cut off, sometimes the lens needs to be stopped down half a stop less which produces a brighter image. Also, depending on the target, the smaller field of view may not be important.

The 1600MM Cool, with its small pixels, is a good match for lenses in the 135mm-200mm range. Even 135mm is enough to resolve good detail on many DSOs, note the dust pillar on the head of the Pelican in the image above.

Hi Neil,

These are great images.

I am buying an asi1600mm for use with a skywatcher 150pds Newton. I am also interested in medium/widefield nebula images in narrowband and I am very tempted by the Samyang 135mm f2 lens and attaching it to the 1600 and filterwheel.

Elsewhere on this site there seems to be discussion about spacers and it being relatively tricky to get focus on the sensor but you have obviously had success !

Would you mind showing me a pic of or a brief description of your setup ? so that I can, quite frankly, copy it?

Best wishes and clear skies,

Andy

[Gina]

I use vintage SLR lenses as used on the Pentax SLR camera, produced by the Asahi company of Japan and called Takumar, Super Takamar and SMC Takamar (Super Multi Coated).

[DaveS]

This is Orion with a 35mm lens on the ASI1600

And a close up of the Sword and flame with a 180mm