Has anyone used the dual split image from jinfinance?

Eruditass · 09-06-2010, 12:05 PM

Originally posted by Lowell Goudge

It arrived yesterday

in my *istD it took less than 2 minutes to install, and in a few test shots, using my cat and his wiskers as the focusing line, it seems to be dead on, with no shims etc. Same as when I got the single split image 18 months ago from Jinfinance. It also seems to be more accurate, or to be exact, the dual split causes more disruption of a straight line than the single split, making minor focusing errors more apparent. the microprism collar snaps into focus very abruptly and as a result is very good for scenes without sharp lines.

I will attempt to assess the centering and spot metering within the next week,

as for AF points not indicated, I will look into this, but if you turn on the viewfinder indication (red dot) it will light up to show you which one is active any way, so I don't see this an issue

I look forward to your results. I wonder if spot-image is off by a certain amount, or has random error.

As for AF points, the K-x does not light up. I'm wondering how easy it is to tell the 11-point locations with neither the brackets, nor the LEDs, just from gauging distance from the circles. Of course, I could just draw in rule of third lines (I believe they correspond to them?) with a fine tip marker.

Last edited by Eruditass; 09-06-2010 at 01:23 PM.

**Lowell Goudge** · 09-07-2010, 05:19 AM

Regarding spot metering, I cant answer yet as I shoot with center weighted knowing the spot was unreliable in the past with a single split

As for focusing points I doubt you can get a fine enough marker to draw lines. Why not just put colored dots?

Eruditass · 09-07-2010, 10:32 AM

My friend has some drawing pens that are 0.2mm that I will try out. I should be able to clean it off if it doesn't work, anyway. Dots is a pretty interesting idea as well, we shall see.

Will this focus screen be completely unusable with my Tamron 500mm f8 such that I have to switch focus screens in order to use it?

imtheguy · 09-07-2010, 11:03 AM

Originally posted by Eruditass

Will this focus screen be completely unusable with my Tamron 500mm f8 such that I have to switch focus screens in order to use it?

You will have black-outs in the center. Not completely unusable but a real PITA at f8.

Eruditass · 09-07-2010, 11:20 AM

Damn. and this is regardless of how bright it is outside?

At least I will retain Catch-In-Focus, but I won't know which way to turn..

imtheguy · 09-07-2010, 11:54 AM

Originally posted by Eruditass

Damn. and this is regardless of how bright it is outside?

At least I will retain Catch-In-Focus, but I won't know which way to turn..

For occasional shots it might work well enough so you don't swap, you need to try it. With the dual-diagonal split screen from jinfinance (same one I use) you don't lose the whole circle, but depending on exactly how your eye is placed on the viewfinder you lose one side or the other of each split. f8 seems to be the point at which you can get some use out of the screen but its not like f4. I was shooting yesterday with stacked TCs that gave me a f8 total and it was difficult to position my eye to use the split but not impossible, just somewhat aggrevating.

Eruditass · 09-15-2010, 04:40 PM

Originally posted by imtheguy

For occasional shots it might work well enough so you don't swap, you need to try it. With the dual-diagonal split screen from jinfinance (same one I use) you don't lose the whole circle, but depending on exactly how your eye is placed on the viewfinder you lose one side or the other of each split. f8 seems to be the point at which you can get some use out of the screen but its not like f4. I was shooting yesterday with stacked TCs that gave me a f8 total and it was difficult to position my eye to use the split but not impossible, just somewhat aggrevating.

I just got my split-image. Good news: Dual-split image looks awesome and much easier to tell if things are in focus. I just tried the f/8 lens indoors and found it quite usable. Well, the shaking made it nearly unusable, but it was not difficult to position my eyes to make it not black out, and I could actually use the split-image to make sure things were in focus! microprism was worthless at f8, though. I imagine outside chasing objects this would be much more difficult, however.

Bad news is looking through my 1.35x magnifier, I can see some defects on the screen. I can see some darker areas, most noticibly a lopsided ellipses around the center. Hopefully I just didn't clean it well enough.

Lastly, I think someone mentioned this, but the circle is a little too high.

Last edited by Eruditass; 09-15-2010 at 04:46 PM.

imtheguy · 09-15-2010, 08:15 PM

Originally posted by Eruditass

I just got my split-image. Good news: Dual-split image looks awesome and much easier to tell if things are in focus. I just tried the f/8 lens indoors and found it quite usable. Well, the shaking made it nearly unusable, but it was not difficult to position my eyes to make it not black out, and I could actually use the split-image to make sure things were in focus! microprism was worthless at f8, though. I imagine outside chasing objects this would be much more difficult, however.

Bad news is looking through my 1.35x magnifier, I can see some defects on the screen. I can see some darker areas, most noticibly a lopsided ellipses around the center. Hopefully I just didn't clean it well enough.

Lastly, I think someone mentioned this, but the circle is a little too high.

Thats great that you have pretty clear circle at f8. My copy, not so much. I can see some faint lopsided shadows but could not tell if it was the screen or the mirror (since i had to use lens cleaner on it once and it left streaks).

Mine too has the circle slightly above the red focus point but you know, its aesthetics. The focus point works in a lot bigger area than just the tiny red square.

enjoy new toy!

09-07-2010, 11:20 AM	#20
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Damn. and this is regardless of how bright it is outside? At least I will retain Catch-In-Focus, but I won't know which way to turn.. Last edited by Eruditass; 09-07-2010 at 11:27 AM.

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09-06-2010, 12:05 PM	#16
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Originally posted by Lowell Goudge It arrived yesterday in my istD it took less than 2 minutes to install, and in a few test shots, using my cat and his wiskers as the focusing line, it seems to be dead on, with no shims etc. Same as when I got the single split image 18 months ago from Jinfinance. It also seems to be more accurate, or to be exact, the dual split causes more disruption of a straight line than the single split, making minor focusing errors more apparent. the microprism collar snaps into focus very abruptly and as a result is very good for scenes without sharp lines. I will attempt to assess the centering and spot metering within the next week, as for AF points not indicated, I will look into this, but if you turn on the viewfinder indication (red dot) it will light up to show you which one is active any way, so I don't see this an issue I look forward to your results. I wonder if spot-image is off by a certain amount, or has random error. As for AF points, the K-x does not light up. I'm wondering how easy it is to tell the 11-point locations with neither the brackets, nor the LEDs, just from gauging distance from the circles. Of course, I could just draw in rule of third lines (I believe they correspond to them?) with a fine tip marker. Last edited by Eruditass; 09-06-2010 at 01:23 PM.*

09-07-2010, 05:19 AM	#17
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888 Original Poster	Regarding spot metering, I cant answer yet as I shoot with center weighted knowing the spot was unreliable in the past with a single split As for focusing points I doubt you can get a fine enough marker to draw lines. Why not just put colored dots?

09-07-2010, 10:32 AM	#18
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	My friend has some drawing pens that are 0.2mm that I will try out. I should be able to clean it off if it doesn't work, anyway. Dots is a pretty interesting idea as well, we shall see. Will this focus screen be completely unusable with my Tamron 500mm f8 such that I have to switch focus screens in order to use it?

09-07-2010, 11:03 AM	#19
imtheguy Site Supporter Join Date: Mar 2009 Location: Virginia Beach Photos: Gallery \| Albums Posts: 2,950	Originally posted by Eruditass Will this focus screen be completely unusable with my Tamron 500mm f8 such that I have to switch focus screens in order to use it? You will have black-outs in the center. Not completely unusable but a real PITA at f8.

09-07-2010, 11:54 AM	#21
imtheguy Site Supporter Join Date: Mar 2009 Location: Virginia Beach Photos: Gallery \| Albums Posts: 2,950	Originally posted by Eruditass Damn. and this is regardless of how bright it is outside? At least I will retain Catch-In-Focus, but I won't know which way to turn.. For occasional shots it might work well enough so you don't swap, you need to try it. With the dual-diagonal split screen from jinfinance (same one I use) you don't lose the whole circle, but depending on exactly how your eye is placed on the viewfinder you lose one side or the other of each split. f8 seems to be the point at which you can get some use out of the screen but its not like f4. I was shooting yesterday with stacked TCs that gave me a f8 total and it was difficult to position my eye to use the split but not impossible, just somewhat aggrevating.

09-15-2010, 04:40 PM	#22
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Originally posted by imtheguy For occasional shots it might work well enough so you don't swap, you need to try it. With the dual-diagonal split screen from jinfinance (same one I use) you don't lose the whole circle, but depending on exactly how your eye is placed on the viewfinder you lose one side or the other of each split. f8 seems to be the point at which you can get some use out of the screen but its not like f4. I was shooting yesterday with stacked TCs that gave me a f8 total and it was difficult to position my eye to use the split but not impossible, just somewhat aggrevating. I just got my split-image. Good news: Dual-split image looks awesome and much easier to tell if things are in focus. I just tried the f/8 lens indoors and found it quite usable. Well, the shaking made it nearly unusable, but it was not difficult to position my eyes to make it not black out, and I could actually use the split-image to make sure things were in focus! microprism was worthless at f8, though. I imagine outside chasing objects this would be much more difficult, however. Bad news is looking through my 1.35x magnifier, I can see some defects on the screen. I can see some darker areas, most noticibly a lopsided ellipses around the center. Hopefully I just didn't clean it well enough. Lastly, I think someone mentioned this, but the circle is a little too high. Last edited by Eruditass; 09-15-2010 at 04:46 PM.

09-15-2010, 08:15 PM	#23
imtheguy Site Supporter Join Date: Mar 2009 Location: Virginia Beach Photos: Gallery \| Albums Posts: 2,950	Originally posted by Eruditass I just got my split-image. Good news: Dual-split image looks awesome and much easier to tell if things are in focus. I just tried the f/8 lens indoors and found it quite usable. Well, the shaking made it nearly unusable, but it was not difficult to position my eyes to make it not black out, and I could actually use the split-image to make sure things were in focus! microprism was worthless at f8, though. I imagine outside chasing objects this would be much more difficult, however. Bad news is looking through my 1.35x magnifier, I can see some defects on the screen. I can see some darker areas, most noticibly a lopsided ellipses around the center. Hopefully I just didn't clean it well enough. Lastly, I think someone mentioned this, but the circle is a little too high. Thats great that you have pretty clear circle at f8. My copy, not so much. I can see some faint lopsided shadows but could not tell if it was the screen or the mirror (since i had to use lens cleaner on it once and it left streaks). Mine too has the circle slightly above the red focus point but you know, its aesthetics. The focus point works in a lot bigger area than just the tiny red square. enjoy new toy!