Canon 600 /4 IS L vs Mid end telescope

[Percy]

http://www.samirkharusi.net/televue_canon.html

Results weren't surprising to me, but it might open some eyes out there.

Percy

[markesc]

Wow!

I thought I was a photographer until I read that! Great review!! At the end of the day, would you say the Canon Lens is worth the $ ?

Here is my work, I usually shoot just landscapes though! I wish I had that Canon lens for Comet McNaught!! ( I only have a 70-200IS L with a 2x <-- which I badly wish to trade for the 1.4x) 5D and 20D.

www.scenicserenity21.com

[Percy]

If you're after terrestrial objects and need autofocus, then the Canon is worth the money. For a mass produced optic, it's not too bad. But when compared to a mid level telescope, it lacks in many ways, one of them being optical QUALITY.

I've had to rebuild a 70-200 2.8L lens recently, and the engineering behind it was quite good. Fairly robust in construction, engineering, choice of lubricants, etc. They were using a slightly raise plastic insert under a cam mechanism to help smooth things - even if the lubricant was completely worn out!

So, with the 600/4 L IS, you're paying for the engineering. Magnesium body, excellent fit and finish, and something that will take the rigors of pro usage. Plus very fast autofocus. (the AF motors, USM, are working at around 40,000 times per second - ultrasonic vibration to move the rotor...very cool.)

If it was an AF Nikon vs AF Canon, it would be a whole different ball of wax. Both would be mass produced optics, but in terms of fit and finish, durability and reliability, I would give it to the Canon, hands down. I've seen far too many mechanisms fail with Nikon lenses.

Comet McNaught really needs something on the order of 1000+ mm to be framed adequately. Now if you're in the southern hemisphere enjoying multiple tails, then a 50mm will do nicely. When it was visible to us in the north, only a single tail was visible.

Percy

[RA40]

Interesting findings. I don't like that heavy 1 Series body un-supported like that. Even a thick walled tube may show flex allowing degradation of image quality. IMO.

Seeing these astro shots motivates me to do some next time I'm out. I'm frequently in the back areas of wine country and there is minimal light pollution to deal with.

[Percy]

Mike,

The lens interface between the 600 and the EOS 1 is good...that's why they made the lens mount larger. BUT, I can see what you're talking about with the t-scope and the EOS1 body. With that much extension, there's bound to be flexure in affecting the image. Televue extensions like that are ONLY 1.25 inch diameter. I'm using 2.7 inch diameter - much more stable.

Percy

[RA40]

Percy-

I'd be interested in seeing your rig. Astronomy could be enjoyable for me...just living in this polluted (in nearly every sense) of LA/OC makes some hobbies more difficult.

Way back, we'd drive up to Big Bear or the depths of the desert for quick jaunts. To drive 3 hours to catch a small window of 1-2 hours became tiresome then grab some ZZZ's, then off to work. Those timed exposures, I think we'd only get a roll off at best. I spent some of my time wandering the area, flashlight in hand taking pictures of my light trails.