What Canon lens around 200mm

[gajjer]

I would like to invest (?) in a lens around 200mm for my Canon camera. I have a Sigma 70 - 300 zoom, but I imagine I would do better with a fixed focal length with a big aperture.

Any suggestions?

cheers

gaj

[Knight of Clear Skies]

The 200mm f2.8 is very well regarded and quite reasonably priced for a pro lens, here's an example image I took with one. I picked mine up second hand for about £370. On the other hand the best budget options are probably the Takumar M42 lenses, the 200mm f4 can be picked up for about £30-£50. Hope that's some help.

[Staffs Oatcake]

What's your budget? And what body are you attaching it to? As some of the canon lenses are designed for full frame sensors or 35mm cameras eg 5D. Series where others are designed for the APS-C sensors 350d 400d 40d 50d. Etc.

[laser_jock99]

Don't rule out any of the L-serries (or other manufactures equivalents) 80-200 F2.8 Pro zoom lenses either.

The fast F2.8 focal ratio is fixed thoughout the zoom range and they have ED glass lenses.

I get nice results at either end of the 80-200mm FL, very handy for framing those wide field shots.

Saggitarius at the 80mm end of the zoom

and at the 200mm end.

[cfpendock]

I use a Canon 200mm EFL prime focus lens.  It is f2.8 and gives excellent wide field images.  I use it either directly on the camera Canon 550D, or together with my Atik 4000 camera.  It actually gives slightly sharper images at f4, although without an aperture reducer, this can result in spikes on brighter stars.  Focusing is not so easy, and you will almost certainly need some sort of accurate focusing device as shown below:

Chris

[gajjer]

Thanks for the replies.

Sorry I should have said it's for the 60D. Budget is flexible. I am wondering whether I should be thinking of something to use with the Atik 383L too.

If it was just for the Canon I would say £500 and for both possibly £1000.

I can always make any adapters necessary.

Nice pictures Knight of Clear Skies. I'd be quite happy with those.

Is there a comparison chart anywhere. When searching it's a bit of a pain having to look at the individual specs to find what focal length telescope lenses are.

Perhaps FLO can advise me. A simple table please?

cheers

gaj

[Staffs Oatcake]

Check out Canon's own website. They have a huge selection of lenses to meet all budgets.

[gorann]

Here is an excellent site that seems to tell you everything you need to know about almost any (current) camera lens:

http://www.photozone.de/

[wxsatuser]

Here is an excellent site that seems to tell you everything you need to know about almost any (current) camera lens:

http://www.photozone.de/

Seconded!

There aren't may lenses that cut the mustard but this site will tell you where to spend you hard earned.

It will tell you that some good lenses will cost an arm and leg and some will shock you at their low price.

[laser_jock99]

I use a Canon 200mm EFL prime focus lens.  It is f2.8 and gives excellent wide field images.  I use it either directly on the camera Canon 550D, or together with my Atik 4000 camera.  It actually gives slightly sharper images at f4, although without an aperture reducer, this can result in spikes on brighter stars.  Focusing is not so easy, and you will almost certainly need some sort of accurate focusing device as shown below:

Chris

IMG_1607.jpg

Stopping down to F4 is good idea as you'll better stars in the corners (tempting as it is to shoot at F2.8!) .

Another tip is to a round apperture in front of the camera lens to avoid aperture spikes. Also focusing 1/3 of the way out from the centre axis improves corner stars. 

[gorann]

Yes, I just invested a minor sum in step down rings to avoid the star spikes from the internal iris, something like this:

http://www.ebay.co.uk/itm/18pcs-Step-Up-Down-Lens-Filter-Ring-Adapter-Set-37-82mm-For-Canon-Nikon-Metal-/271947418156?hash=item3f51544a2c:g:4~0AAOSwrklVbXKc

[gajjer]

Thanks everyone. Some great pictures and that link is brilliant. Lots of data.

I have a Sigma 105mm f2.8 macro it looks like I might get reasonable results from that before I commit.

Laser Jock99. You have me wondering about a zoom now!

I really didn't expect that sort of quality from the DSLR.

Sounds like focus may be a problem though. Is there any focusing aid for a DSLR?

cfpendock - what is that focus mechanism?

Thanks all. I appreciate your advice.

cheers

gaj

[cfpendock]

cfpendock - what is that focus mechanism?

Thanks all. I appreciate your advice.

cheers

gaj

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p3286_Microfocuser-and-focus-lock-fuer-camera-lenses-up-to-D-135mm.html

Absolutely essential in my opinion.

Chris

[gajjer]

Thanks Chris

Clear the workshop I'm coming in!!

Another project for cloudy nights!

One more question. What do you use to connect the lens to the camera?

cheers

gaj

[carastro]

How can you tell what the focal ratio is for a lens?

Carole

[cfpendock]

Thanks Chris

Clear the workshop I'm coming in!!

Another project for cloudy nights!

One more question. What do you use to connect the lens to the camera?

cheers

gaj

Well, for the Canon camera obviously it is the normal bayonet fixing.  For my Atik 4000 it was more complicated because I needed to include a filter drawer ( http://www.teleskop-express.de/shop/product_info.php/info/p2165_Filter-Quick-Changer-incl--1x-1-25--filter-drawer---low-profile.html ) and I had to have a special adapter made to suit.  For your Atik 383, I believe teleskop service make some adapters:  http://www.teleskop-express.de/shop/index.php/cat/c132_T2-M48-and-C-Mount-Bayonet.html

Chris

[ollypenrice]

How can you tell what the focal ratio is for a lens?

Carole

Normally you just set the F stop you want. F stop is focal ratio.

If making a mask you know the FL so you simply measure the clear aperture and divide the FL by that. This is the way to work out the size of aperture mask to cut for each F ratio you want to try. It will only be approximate for various reasons but will give you an idea.

I thought the Canon 200L prime was excellent with the mask above. The problem was that my 7.2 micron CCD pixels were just too big for it.

The TS focuser is great if you're not using the Canon focuser.

Olly

[carastro]

Thanks Olly, although I have been imaging for 6 years now, camera lens imaging is something I am trying to get into having jumped that and dived straight into scope imaging, and I really don't understand camera lenses at all.  I have just bought myself a Canon Zoom EF 28-200mm f/3.5-5.6 on Ebay (I know Zoom is not ideal but it was £400 cheaper than the new fixed 200mm lens I was pointed to and it means I can vary the amount of zoom.  Also I now notice the F number was in the Ad doh!

But am really starting like a beginner with lens imaging.  

I am doing this so I can do some imaging when I go on holidays with an Ioptron Skytracker.

Watch this space.

Carole