?? Best Non "L" Canon lens for Astro work??

[dugnsuz]

Hi All,
I too have just upgraded from my Pentax to the new Canon 40D DSLR.
The L series lenses are way out of my budget right now so I hope some IIS members can advise on the best non-L lenses to use for astrophotography.
The 50mm f1.8 seems a no brainer for the price. But, I'm wondering about the CA in the the 85mm f1.8 and 100mm f2 lenses.
Any information appreciated.
Cheers
Doug:thumbsup:

[[1ponders]]

You could try the 50mm f/1.4 (?). Much better quality but yes more expensive. What is your budget?

[[1ponders]]

Check out this thread http://www.iceinspace.com.au/forum/showthread.php?t=21245&highlight=lens

[acropolite]

From what I've read the difference in optical performance isn't worth the money, although I haven't tried either.

[dugnsuz]

Paul - looking at around $600. I want something longer than the 50mm lens, 1.4 or 1.8!

ebay options are:
85mm f1.8 USM
100mm f2 USM - worried re this one, one review site has many negative comments on the CA at f2
100mm f2.8 (macro)

Comments? Thanks for the link, very helpful
Doug

[dugnsuz]

ps...
re the 50mm f1.8 - is it difficult to focus at infinity with the very small unmarked focus ring? Is the f stop ring easy to use?
Cheers
Doug

[avandonk]

The Canon 85mm F1.8 would be sharp out to the corners with a C size sensor wide open at F/1.8.
At f/2.8 only has slight aberration at corners on the full frame 5DH.

Bert

[iceman]

I went through this process too.

I've got the 50mm f/1.8 and the Sigma 17-70. Both great value and good quality.

[dugnsuz]

Thanks Bert, Mike
Got the kit lens that came with 40D - EF 17-85mm f4-5.6 IS USM...great for daytime, pretty impressed and the image stabiliser function is nifty!! Haven't had a chance to give it a good try under the stars yet.
Really after a decent prime lens around 100mm for wide fields, although I reckon the 50mm f1.8 is a "must have" too
Cheers
Doug

[[1ponders]]

It can be a challenge to focus, but then any lens manually focused can be a challenge. The 50mm is very light on the touch though so I usually stick a piece of blu-tac or similar against the focus ring and lens body to add a bit of resistance. Makes the world of difference. Then again so does DSLR Focus ;) (Unfortunately I don't think it works with the 40D)

I've read a few reviews of the 100 and most seem to be pro rather than against. Here is a variety. http://www.fredmiranda.com/reviews/showproduct.php?product=33

Don't know how unbiased this one is with all the adverts at the bottom
http://www.photozone.de/8Reviews/lenses/canon_100_2/index.htm

But for $600 I think you will be hard pressed to better it, though the 100 macro (not the soft focus) it a damn fine lens by all accounts

[dugnsuz]

Hi Paul,
Yes I've seen this set of reviews - it's the first 10 or so that have me worried.
They all comment on "horrific CA" in some way or another. They also comment on how sharp the lens is too! A few of my Pentax lenses exhibited bad CA on brighter stars, and although I know that it can't be eliminated at my price point, I want to be sure I'm not buying my way into similar problems.:shrug:. Spent far too long trying to remove purple halos in PS - life's too short:lol:.
Is the only route the "L" way!!??:P
Cheers
Doug:thumbsup:

ps the 100mm f2.8 macro is a wee bit more expensive than $600, even on ebay

[sejanus]

if you can save up a little more, the 200/2.8 prime would be a good choice, or if you are patient i've seen them go on ebay for 650

btw you can get the 50/1.4 for $499 from http://www.d-d-photographics.com.au or a little less if you import it yourself

don't feel bad about getting a 50mm non L lens, I have the $1700 50/1.2 and it's not as sharp as the 1.4 or 1.8 stopped down a tad - but it does have other qualities :p

[davewaldo]

Hi Doug,

I work with several other pro photographers at a studio in Brisbane. One lens we always recomend (and our studio has 3) is the 100mm macro. It really can't be beat. It easily performs at a "L" level but without the body quality (not an issue unless your a press photographer) or the price tag. We use this lens a lot for commercial advertising and product photography. Its one of the sharpest lenses canon makes, including L series.

I must say though that I have only used it for "land" use and have not tried it on the stars. But I would imagine it would perform well.

I could always do a quick test for you on the weekend..... (I don't have a GEM but could do some quick exposures)

Also I would 2nd Phils comment in saying that the 50mm 1.4 is not really worth the extra money for image quality alone. It is biult better and has a distance scale. I own the 1.8 and love it for its cheap/nasty feel but lovely images.

Hope this helps.

Dave.

[sejanus]

not too sure about the 100. it's certainly a ripper of a lens but macro lenses are typically optimised for relatively short distances, not really for infinity.

[dugnsuz]

Eat those words!!!:P:P
I thought that might be the case too until I saw this pic by Terry Lovejoy (cometguy) taken with the 100mm f2.8 macro lens!!!!
http://www.pbase.com/terrylovejoy/image/36529489

It's pretty damn good!
Cheers
Doug:thumbsup:

[Benny L]

generally non-L is not a part of my vocabulary, but is i was to buy one it would be the 100mm f2.8 macro

[dugnsuz]

Hi Dave,
Thanks for the response - I really like the FOV delivered by a 100mm lens.
The f2.8 macro will be pushing the budget, the EF 100mm f2 USM model is more my price!
Do you have any experience with that lens in your work?
Also the 85mm f1.8 USM looks tasty too!!
Cheers
Doug:thumbsup:

[dugnsuz]

Thanks for the heads up Benny
Doug:thumbsup:

[[1ponders]]

Bring it up to my place Dave and we'll have a play :D

[dugnsuz]

Mail it to my place and I'll have a play:P:D:P:D:P

[[1ponders]]

I just thought that if he brought it up here we could do a side by side with the 135 f2L :D and see if you still wanted the 100 after that :P

[dugnsuz]

You are a cruel man Paul!!!:lol:

[Garyh]

Don`t know if you have seen these reviews Doug but I find them very good and in depth.

http://www.photozone.de/8Reviews/index.html

All the lenses you have mentioned all look like keepers..
I went for a 200 2.8L and its a beauty! Would love to get the 85/1.8 or the 100/2. I don`t think you can go wrong with any one you get..
cheers

[davewaldo]

I'd love to come for a play and do some wide fields Paul! I'd also like to test our 70-200 f4L lens and even our 16-35 2.8L II lens (although I think the latter would be crap for astro).

Doug, the macro is the only non L lens we use, which is saying something. I have no experience with the other lenses you mention sorry.

Canon does however publish MTF graphs for all their lenses... if you look up these you should get an idea of the performance. Perhaps look up some L lenses so you can see what sort of graph you are aiming for.

Here is a link to the US canon site which has MTF graphs for their lenses:
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=155&modelid=7400

Enjoy!

Dave.

[dugnsuz]

Thanks all for the help,
It all now depends on someone buying my pentax DSLR on ebay!!!!!!
I think it's down to the 3 I mentioned above - 85mm, 100mm f2 and 100mm f2.8
Cheers
Doug

[dugnsuz]

Thanks Gary and dave for the links
Doug

[CometGuy]

Doug,

I've heard the 100f2 is very slightly better than the 85 f1.8 (a number of people on the digital_astro list have commented about this, I don't actually have either lens). Between the 100f2 and 100f2.8, if you didn't have a requirement for macro I would problably go with the 100 f2. Although the 100f2.8 is very sharp, it is quite a long bulky lens (its nearly the size of the 200 f2.8).

Terry

[dugnsuz]

Agreed Terry,
the 100 f2 has a very small footprint(:P) compared to the f2.8.
But I am still worried about the "horrific CA" commented on in many of the web reviews - those guys are commenting on bright objects in daylight, the stars are even more critical on lens flaws...so I worry!!!.
And, as IIS member Dave has stated - the f2.8 is the only non L lens they'll use at his pro studio...And!! that pic you took is a beaut!!!
Signed
Confused from Hahndorf
Doug:thumbsup:

[CometGuy]

Doug,

Well I don't think you will be dissappointed with the 100 macro.

Terry