[RJM]

We have been using this combo exclusively for about 3 weeks now for whale watching in Hawaii, with me primarily on the Nikon and the wife with the Canon.

Just before sunset, I picked up the Canon to observe a fishing boat at mooring near the horizon. Right away I noticed the Canon was noticeably LESS BRIGHT than the view thru the Nikon.

This was somewhat interesting since it has a slightly larger exit pupil and with a two eye-ed view, SHOULD appear brighter. The Nikon at 20x does have a higher twilight factor but that should only affect details seen under low light.

Anyway, I had never compared them in this way before so more observation is called for.

[brocknroller]

Aloha Rick,

Very interesting observation. I wonder if the reduced secondary spectrum in the Nikon ED50 made the views appear brighter?

I've noticed this in comparing ED and non-ED bins even when comparing two versions of the same bin, one with ED glass and one without. The ED version looks brighter, because the colors are more vibrant. Perhaps the shift of light in the red toward sunset made this more noticeable.

A good place for a comparo would be on the Kilauea Volcano lava flows, lots of bright color against a dark background. There have been two eruptions in the past 24 hours. Check out the Website:

http://volcanoes.usgs.gov/hvo/activi...aueastatus.php

Tiny Bubbles

[Hermann]

I only had a chance to have a look at the 18x50 once, and that was a couple of years ago. My impression was that it was pretty dark. I also recall reading some reports that it had noticeably lower transmission than the 12x36 or the 10x30. The ED50, on the other hand, seems to be pretty good in that respect.

Hermann

[KorHaan]

Canon 18x50 has two UD-lens elements also, Ultra-low Dispersion as it says in the manual. The Nikon 50ED should have no advantage there.

Interestingly, I have a completely different experience than Rick with these two optics.
I've used a birders Nikon 50ED under an overcast sky, and my own Canon 18x50's were noticeably brighter. The Nikon had the zoom eyepiece, mind you, that may make a difference in brightness as opposed to the 20x fixed EP. The 20x EP is likely to be brighter.

I also tried the Nikon 50ED once in a store, on a bright sunny day, and the image didn't impress me like the Canon 18x50's did on a bright sunny day. The Nikon 50ED in the store had the zoom EP also.

When comparing the 18x50's to my Canon 10x30's I readily noticed the 10x's greater transmission. Both bins' exit pupils are not that far apart in size that it would matter significantly, 2.8 vs. 3, respectively.

Best regards,

Ronald

[RJM]

It may not be brightness afterall but a color cast. I really need to wait until I get back to Japan next week to do some controlled testing as the vog here makes sunsets kinda wonky.