filters

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speedy21
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filters

Post by speedy21 »

How do you use filters on a Dslr camera I have standard is it 1.25 eyepiece and a couple of filters but there to small to fit to the eyepiece and a 2inch looks like it would be to big any help would be great
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David Frydman
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Re: filters

Post by David Frydman »

What is the lens filter thread diameter?
You can use step up/down rings but eyepiece filters may have a different pitch?

Regards,
David
speedy21
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Re: filters

Post by speedy21 »

Thank you will have a look in to that would a filter wheel help
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mike a feist
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Re: filters

Post by mike a feist »

Using filters on cameras, telescopes and spotting scopes. I have only over used neutral Moon-filters on astro-scopes which fit in the thread of the standard eyepiece. I did try once to experiment to seeing if I could fit photographic filters on the front of of spotting-scopes, which often have a thread which hold the object-glass in place ( These often do not have replaceable eyepiece and one cannot fit the usual filters.) Invariably, although they seemed almost to fit, with the diameter correct, the pitch of the thread was wrong and failed to screw in.
Interestingly, recently I acquired of a pair of Russian binoculars, through a the family member who had recently died, and these where supplied with two clip-on yellow eyepiece filters for use in bright sunlight and misty conditions - so says the instruction sheet. By some fortunate chance I found that one just fits in the rubber eyecup in front of the eyepiece of just one of my spotting scopes. Obviously not much use for faint objects but seems advantageous in looking at the Moon and other bright objects especially when viewing against blue skies etc. regards maf
Brian
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Re: filters

Post by Brian »

Hi Speedy.

I don't have a detailed picture of the set-up you are trying to put together, so a little more info would be very useful I think.

As said earlier, 1.25 inch-fit eyepiece filters should screw onto the base of any 1.25 inch eyepiece which has a thread, and these days most eyepieces do have this thread. The same applies to 2inch-fit filters and 2 inch diameter eyepieces. Bear in mind you won't need to use an IR-cut filter with your Nikon as it's already built-in to the camera.

I see that you mentioned a filter wheel, so are you thinking of doing RGB imaging with your Nikon and a Red/blue/green filter set? If so this probably won't give you the results you want/expect. The Nikon is a one-shot colour camera (OSC) and has a Bayer matrix fitted over the sensor. The Bayer matrix is an array of microscopic red , blue and green filters which allow only certain wavelengths of light to illuminate certain pixels. If you then restrict the colour of the light hitting the Bayer matrix by using narrow-band red, blue or green filters on the front of the camera you can get the situation where only two out of every 8 pixels are responding to that light, with the loss of sensitivity that entails.

If you are wishing to do RGB imaging then for best results you really need a black/white (mono) CCD to use with the RGB filter set. I think we need to have some more info about just what you want to achieve so that we can give more specific guidance,

Best regards,
Brian
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speedy21
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Re: filters

Post by speedy21 »

I had a go at taking photos of M101 the light pollution and the light from the moon drowned it out you can just make out the image with a bit of playing about what I'm after doing is trying to put in to use of light pollution filters to help block out some of the unwanted light I got some good photos of Jupiter useing my projector adapter and a skyglow filter was impressed so wanted to see if I could do the same for deep sky objects without the projector hope this helps on what I'm after doing
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Brian
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Re: filters

Post by Brian »

Sounds as though you just need to get the correct fitting light pollution filter for your eyepiece. These are available in 1.25 and 2 inch sizes for instance:

http://www.firstlightoptics.com/light-p ... aging.html

Bearing in mind that these filters are not really suitable for cutting light from the modern LED streetlights which are fast appearing everywhere these days,

regards,
Brian
52.3N 0.6W
Wellingborough UK.

254mm LX90 on Superwedge, WO ZS66SD, Helios 102mm f5 on EQ1, Hunter 11x80, Pentax 10x50
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speedy21
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Re: filters

Post by speedy21 »

Nice one thank you will have a look in to them I still have the yellow ones hound me accept on my front street but my house blocks them out witch is a bonus but a a pain on veiwing as only see objects above my roof facing north
Skywatcher 200p explorer EQ5 mount synscan upgrade kit
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