Photon XT 4.6 scope cap mod??

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Krm944
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Photon XT 4.6 scope cap mod??

Post by Krm944 » 21 Mar 2015, 00:04

On a forum over here in the States, I saw one user has modified the scope cap for a 22mm hole when used with an external IR source such as the T20.


Has there been a thread on this?
Thanks

Kyle
Newb to DIY lights (torches)
Super cheapo looking for a deal!

NVOZ
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Joined: 21 Feb 2015, 03:24
Location: melbourne, australia

Re: Photon XT 4.6 scope cap mod??

Post by NVOZ » 21 Mar 2015, 08:23

Hi
I have done this!
Works well, I have a spray paint can lid with hole in end and a IR filter inside cap.
This set up with a t38 works very well! I have the doubler as well, which makes a big difference :thumbup:

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Norfolkngood
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Re: Photon XT 4.6 scope cap mod??

Post by Norfolkngood » 21 Mar 2015, 09:31

I have a 16mm hole in it and it increases the depth of field and cuts down on excessive eye shine .
Oi loik noite soights oi duz

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some bloke
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Re: Photon XT 4.6 scope cap mod??

Post by some bloke » 21 Mar 2015, 10:10

That was something I originally did with the first Photon:

https://www.youtube.com/watch?v=4F-BxiP63MQ

https://www.youtube.com/watch?v=YgiDHbDeglc
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Ash.
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Re: Photon XT 4.6 scope cap mod??

Post by Ash. » 21 Mar 2015, 18:17

I have the standard doubler 22mm hole on mine and that alone works really well. but always wondered if I was to have a play and reduce the size of the hole would improve it a little more?

Norfolkngood
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Re: Photon XT 4.6 scope cap mod??

Post by Norfolkngood » 21 Mar 2015, 20:04

For me the 16mm hole was best on the standard and with a doubler I popped out the inner piece on the lens cap so a 20mm hole. It's some bloke who popularised it.
Oi loik noite soights oi duz

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Brooksy
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Re: Photon XT 4.6 scope cap mod??

Post by Brooksy » 21 Mar 2015, 20:10

The smaller you make the hole, the more you 'stop' the lens down which will give better focus from near to infinity, but you will need a more powerful light to compensate. Landscape photographers use f22, which is a really small iris, but they need to tripod mount the camera as the exposure time increases to such that the shutter will be open for so long, hand holding is impossible without the picture being blurred. Model photographers will use f2, which opens the iris up to its maximum in order to focus on the model and deliberately blur the background, but the shutter speed reduces, they only use lights to pick out all sides of the model. On f22 the shutter may be open for as long as 10 seconds, on f2 it may be as little as a 350th of a second.

Try cutting some cardboard circles out and making varying sized holes in each one, then try them one at a time until you find the one that best suits your shooting range, style and light availability. My preference is 26mm, this gives a focused picture from 10 to 100 yards. Yours at 22mm will be about the same I would think.
The early bird may get the worm, but it's the second mouse that gets the cheese.

Norfolkngood
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Re: Photon XT 4.6 scope cap mod??

Post by Norfolkngood » 21 Mar 2015, 20:19

I guess they have a tolerance, mine are good to 100 yards with a Nightmaster nm400 940nm illuminator so good at air rifle ranges. A worthwhile mod though.
Oi loik noite soights oi duz

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Brooksy
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Re: Photon XT 4.6 scope cap mod??

Post by Brooksy » 21 Mar 2015, 20:39

If you want to vary your iris size, buy a cheap UV filter from a photography site, mine is a 62mm thread, then unscrew the retaining ring and cut out a circle with your iris size in it and put it into the filter housing then replace the glass and the ring. You can then have as many sizes as you like and change them to suit your needs.
The early bird may get the worm, but it's the second mouse that gets the cheese.

Krm944
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Re: Photon XT 4.6 scope cap mod??

Post by Krm944 » 21 Mar 2015, 20:55

Brooksy wrote:The smaller you make the hole, the more you 'stop' the lens down which will give better focus from near to infinity, but you will need a more powerful light to compensate. Landscape photographers use f22, which is a really small iris, but they need to tripod mount the camera as the exposure time increases to such that the shutter will be open for so long, hand holding is impossible without the picture being blurred. Model photographers will use f2, which opens the iris up to its maximum in order to focus on the model and deliberately blur the background, but the shutter speed reduces, they only use lights to pick out all sides of the model. On f22 the shutter may be open for as long as 10 seconds, on f2 it may be as little as a 350th of a second.

Try cutting some cardboard circles out and making varying sized holes in each one, then try them one at a time until you find the one that best suits your shooting range, style and light availability. My preference is 26mm, this gives a focused picture from 10 to 100 yards. Yours at 22mm will be about the same I would think.

Thank you for explaining the how and why!! I'm a super novice at photography and even then no one has explained this concept quite as well!!!
Thanks

Kyle
Newb to DIY lights (torches)
Super cheapo looking for a deal!

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