Hi Dave,
thanks for your detailed reply, - though I have to say it sounds very much like you're light years ahead of where I am photographically
My hypo purchase would primarily be for daytime terrestrial use, but I did think it might be nice to dabble at night too. I don't want to mislead you (or anyone), and just as I'm a novice at daytime pics, so too I am a complete beginner at astro. I understand the terms because I've been reading what you guys have to say on here for yonks. But am only just starting to want to put it into practice.
You make an interesting point re the age of the design of the IS feature on the 100-400. Is there a more recent version of essentially the same lens that you know of? Or does it not really make that much difference?
The zoom feature compromising clarity, as you say, shouldn't really surprise us. How many times have we read on here to stay away from zoom binoculars for the same reason. I do make the assumption that this is a reasonable comparison. If it's not, just put it down to my noobness
Your last paragraph about "two stops worth etc etc" was a bit over my head, and with regard to the panning also. But all in good time.
Thanks for all your tips and advice Dave
Quote:
Originally Posted by naskies
Would your hypothetical purchase be strictly for astro use, or daytime as well?
The others have pointed out the many strengths of the 100-400... I guess I'll play devil's advocate and point out a few potential weaknesses I have a bunch of Canon zooms and primes (from 14 mm to 200 mm), but I haven't used the 100-400 or 400/5.6 specifically. I have noticed that the zooms fare a fair bit worse than the primes in terms of image quality (sharpness, chromatic aberrations, flare/ghosting) on stars - but it's nowhere near as noticeable for terrestrial work.
A quick look at The-Digital-Picture.com's database shows that the 100-400 is quite impressive wide open in the centre at 400 mm, but the corners are pretty average (as expected) on a full-frame camera. Probably not a concern if you're on a crop camera.
http://www.the-digital-picture.com/R...mp=7&APIComp=0
Here's the flare comparison. Again, it's more of an issue for full frame than crop bodies.
http://www.the-digital-picture.com/R...mp=7&APIComp=1
IS is super useful on telephoto lenses. The 100-400 is a relatively old model (1998), so the IS is an early generation - only 2 stops worth of compensation (the newest lenses are 4 or more), and no panning mode. Not a deal breaker at all, but it's worth being aware of.
Have you considered the new 70-300L?
If it were me, I'd probably choose the 100-400 for its versatility and IS if it wasn't primarily going to be used for astro work. |