Spotters Color Distortion

[DocRDS]

So i was actually using my spotting scope (Nikkon Low end something) to do some looking at Stars last night and I did see some aberation (not sure if the right term) of the colors. It was actually a good test as I had a fairly "white" object in the middle and I could see a blue and red distorion like a 3 ring venn diagram out of Juptier (white circle) at high power (on a very black background). Now this is not a high end spotter--it was a spotter on a budget from my budget years--job is to see holes. In fact, at my ranges, I usually just use my scope--I think the max mag is 50X or something (on the spotter) maybe even less.

But as I go out farther is this kind of distortion an issue--in bright daylight its my guess that it is unlikely (maybe not) i could see this distortion. I have not had a chance to push distance much past 400 yards so my realm is rather limited, but with all things we grow and soon I will be pushing past those yardages.

Maybe time to upgrade?

(and yeah i'll get a dedicated telescope--different discussion. No really of interest to most people here).

 

[Denys]

I believe what you are describing has more to do with coatings than Chromatic Aberration, though I am happy to be corrected. This must be a very low end Nikon scope as they are usually very good with coating (or it's a much older model.) This will be most apparent on a black background with individual points or spots of white light. Exactly what you saw in the scope. I doubt you will be seeing that in daylight looking at objects and so on.

 

[ma smith]

Problems like CA often show up against edge contrast -- usually black against white.

This could be ommon at night witht he black sky and a white star, or during the day if looking at something artificial like a optician test target. Natural situations, in reality, during the day, its not so much apparent...

Some other things things like power lines or telephone poles against the blue sky can display it, or if you are wniter snow will often set it off against stark shadows, wet trees or dark rocks etc.

IMHO it really matters when its cognitively distracting and/or the edge contrast mess messes up the information content (image sharpness is limited to some extent by available edge contrast).

(Just some random $0.02 worth of thoughts)

 

[Glassaholic]

What you describe is chromatic aberration (CA) and is common in "cheaper" scopes. This is something that really good telescopes correct for (and really good spotters and rifle scopes, bino's etc). Will you see CA through your spotter during the day, yes you will if the contrast difference is high enough (white snow against dark ground/tree bark). For a quick read on CA check out this link (it is for photographic lenses but the same principles apply with all optical devices intended to transmit light to your eye/sensor):

What is Chromatic Aberration?

photographylife.com

PS - the alignment of Saturn and Jupiter was pretty cool to look at last night.