New to using a 'PEEP & GLOBE' at 50 yards...

[Harry Tobin]

Another bit of optics lore: The very small iris reduces the amount of light your eye receives, which it compensates for by opening its' own iris, (the pupil). Exposing more of the cornea, (you eye's objective lens) also exposes more irregularities in the curve of the cornea, reducing the sharpness of the image. More light, smaller opening in your pupil, gives you a sharper image on the retina. Probably not a big factor here, but worth knowing about. I've often wondered if this isn't the main reason for keeping both eyes open when sighting.

Interesting concept, so the more light the better? I read that the Olympic shooters also use color filters on aperture sights that are adjustable colors. They try different colors till they find one that makes the eye to work the best. Now do the colors bend the light waves to benefit the human eye?

[uscra112]

I never heard about that. I do know that the human eye is most sensitive to radiation in the yellow range of the spectrum. This is why skiers, pilots, and rally drivers use yellow lenses on cloudy days. In the yellow range, the eye sees contrast better.

And part of the reason these "blue" halogen headlights are such a crock. They put out a lot of light, but in a wavelength range the eye can't use effectively. OTOH these new LED headlights blind you for a different reason. The LED emitter is too large to be focused properly, so they blast light into oncoming drivers' eyes instead of putting it on the road. Sorry to go so far OT, but LED headlights are a pet peeve of mine.

[303Guy]

I know what you mean about the headlights.

I did discover that certain wavelengths focus clearer than others. I have this reflex sight that has green or red reticle selection. Green is nicer but red is sharper and without reticle distortion which looks similar to orifice distortion. Yellow might be trickier than red because it can be a single wavelength or a mix of red and green.

[uscra112]

I know what you mean about the headlights.

I did discover that certain wavelengths focus clearer than others. I have this reflex sight that has green or red reticle selection. Green is nicer but red is sharper and without reticle distortion which looks similar to orifice distortion. Yellow might be trickier than red because it can be a single wavelength or a mix of red and green.

Yellow filters don't let any red or green through. The business about mixing red and green is for working with pigments, which absorb and scatter light. How the eye sees mixed pigments as a color that neither of them is is above my level of comprehension, but it happens. Make a simple spectrometer sometime. Let sunlight shine thru a narrow slit, and disperse the beam with a wedge prism unto a white sheet of paper.

[Harry Tobin]

This is the video I saw with light filters, this style of shooting is like F1 to car racing.

[OS OK]

I got sidetracked yesterday and didn't practice . . . .

My scope rings for the CZ452 11mm rail came in so I mounted the scope and got her dialed in for the 50 yd. line...



I started drawing up a grid to do the 'node search' with the Harrels Tuner.



I am thinking of doing it sorta like this guy did.



I'm not going to abandon this 'Peep & Globe' thread yet...I haven't achieved my objective yet but, there's another thread a'coming and it's going to be all about the CZ & learning about 'f-class'.

[OS OK]

Got my practice in with the MKII.... Started early today with a dead calm morning & pretty good results.

I stopped fighting with the diffraction issue, closed the iris one click smaller and just dealt with it. Notice I got the 1" white stickers in the mail yesterday with the scope rings for the CZ...those smaller center spots were a big help also.



Got the 'Node Search' done too. This is just a cursory look at where there is possible nodes, I skipped 4 clicks in between each setting, tomorrow I'll figure a good way to search in-between where you see obvious nodes here...



There are 24 settings in each revolution of the Harrel tuner...there are 5 revolutions between '0' & '5' on the scale, for a possible total of
(4 x 24) x 5 or 480 clickable settings. Me thinks? It's confusing at times.



Anyway, enough about the CZ, I have enough material now to get that new thread started and not confuse this thread with it.

[tazman]

Looks like you have some really good things going on now.

[dverna]

I am both astounded and horrified by that many setting on the barrel tuner. Never seen one before so it is interesting.

I can see thousands of rounds expended to sort out the best setting. The smaller the difference in group size between settings the more rounds needed to discern a difference. And then there is the lot to lot difference even when the "right" ammunition is found.

I will be following your other thread with interest as well!!!

[OS OK]

Not much to report today ... it was one of those days I guess that I wasn't holding my mouth just right ...

[OS OK]

Tuesday's Target... This was a day spent with HARRY TOBIN'S LATEST CREATIONS... hahaaa...Harry has a brain-fart and creates a new globe on his 3-D printer, sends them cross country to me and I test them. Great combo of friends helping friends, me thinks.

This is what arrived in the Post Office earlier that morning...



I didn't give the 'star configurations' several days of trials as the open parts of the stars were picking up target spots either in the top or bottom row, depending on which row I was working. That was distracting, my eye kept looking at that anomaly...I threw some fliers as a result, but the inner solid parts of the '7-point' star did point to the spot and that made it very easy to see the spot 'well centered' within the globe.
Can't say for sure but parts of the open groups suggest that to me.



I started with the 7-point star, top row and bottom right spot (I labeled each spot '7-S', '4-S' & 'Post')...then I switched to bottom center & a 4-point star, then to the post on the bottom left. Lot's of fliers generated by me...

Here in the second go-round, I patched the target up and and shot the post-globe on all spots.
I like that post, it is much less distracting to have the globe sitting atop the post instead of having the two horizontal supports of the globes I have been shooting before this.
I suggested that Harry thin that width of the bottom post and we will go at this test again.



'Bottom row fliers' ... I shot from bottom right to left, on each spot I opened the iris one click larger and was getting a more clear sight picture each time. When I got to the bottom left I sent one pretty wide @ 4:00, then it suddenly dawned on me that I had that iris so wide open that I was seeing the inside of the tube that the globe is mounted in. It is shaded in that front sight assembly and I thought my sight picture was good when it really wasn't.
Wish they had made that assembly a tad bit larger.

[OS OK]

Harry Tobin... Sent another of his globe creations on his 3-D printer. "Thank you Harry!"




We have rain this week but I will test this little gem ASAP.

[303Guy]

That's interesting. Looking forward to how it works.

Just a thought, would you be able to fix a star aperture in front of the iris and open the iris bigger? Hold it in place with tape or something?

My experiment for Sunday will be a pin hole on my glasses. Well, these are pin hole glasses but what I've done is block off the surrounding holes. I've tried them before but with all the holes it was distracting and difficult to use but it did work.

[OS OK]

The way I understand diffraction is that it's happening at the iris, in my case, it's the 12 area that it is most apparent. Harry thinks that by intensifying the amount of light in that area before it enters the iris there may be some clearing up of the sight picture.

I don't know? I'm willing to try most anything to perfect the use of the Peep & globe. I believe that with excellent skills launching these lil'pills, one can rival the use of a low power scope.

[303Guy]

What about a red, amber or yellow filter in front of the rear sight? Amber shooting glasses might help. I have a pair but for some reason don't use them. Maybe they didn't help. I should try them again.

[OS OK]

It isn't the color of the light, it is the small diffracted waves of light that turn at an angle at the very edge of the iris opening that cause what I've been referring to as that 'lint' look. Looking like a small piece of lint is in the iris.

The light spreads around the edges of the obstacle. This is the phenomenon of diffraction. Diffraction is a wave phenomenon and is also observed with water waves in a ripple tank. seen in a video below...



Above...water waves coming through a wide slit (the iris in a peep)...

compared to a narrow peep where the light is distorted, 'diffracted' to a greater extent.



From this video below. . . Apertures and Diffraction - Exploring Wave Motion (3/5)

https://youtu.be/BH0NfVUTWG4

It's Harry Tobins... contention that we may be able to add more light to the waves coming through...uhhh, 'intensify the light' somehow other than opening the iris peep so much that you see too much of the front sight sassembly itself.
I don't know myself, Harry is the Brainiac in this family & I'm the brainless guinea pig...the pig wins though, he gets to shoot a lot! .

EDIT: Another video using a laser and a round iris to show the diffraction.

https://youtu.be/uohd0TtqOaw Diffraction Demo: Single Slit and Circular Aperture

[Harry Tobin]

Now when you think about, it is the sharpest when the pupil is small. So my argument has been let more light to the eye. To do this we need to open the peep iris so we get more light. When there is a lot of bright light, the eye iris reduces the size of the pupil to let cone light receptor cells and provides the sharpest vision. Iris, the pupil, which opens and closes to adjust how much light can enter. So it is a balance of the sight picture, open the iris peep and use the outside of the front globe as a centering device. By moving the eye back and forth you can achieve a glow around the front globe, then the sights are aligned. The river is narrow and you have a lot of velocity and when the river opens up it moves without a ripple. But I’m just crazy that way!

[303Guy]

I am very familiar with the lint in the rear sights. When you mentioned cleaning the sights a number of times I chuckled. The number of times I've done that! I didn't realize what it was until you mentioned it! I thought "Damn! There's just no more denying I am getting 'older'!" But I deny it anyway!

Anyway, what I've noticed is that the 'v' sight seems to give the least lint and best refractive focus of the front sight. I've mentioned before that I cannot focus on the front sight - I focus on the target. Well, it seems I am not alone and one target shooter has actually said to focus on the target. But he was talking about aperture sights.

Ok, so the principle of closing the pupil for better focus. Well, having little control over the amount of light, I am trying the pin hole glasses trick. Other posters have tried it too and I think with success.

Something about open sights and my eyes - I can aim quite nicely with 'v' sights or even a notch sight if I am in deep shade, aiming outside in daylight. When I get to the range and there is no longer deep shade then not so much.

[OS OK]

I finally got out today after 3 days of rain & cold...it's still cold but got some sunshine to go with it.
Wasn't one of my best days but I got to compare one of Harry Tobin's Creations up against another he made that seems my favorite at the moment.



The top row was with my favorite globe...a post & globe '.385" x .110" & the notched globe is a '.353" x .110" did the bottom row.
This wasn't much of a try-out for it but already I can see that's it's 'too busy looking', sorta distracting & the lint look/diffraction was still at 12:00, in fact I think the diffraction came deeper from 12 and into that slot. I think that's what I saw.
I wasn't on my game too well today, one of those days I was glad to be done shooting.

The fresh mopped barrel put the first warmer shot over on the 11:00 side instead of the usual 3 to 6:00 area outside the target...but they got in line pretty quick after the first warmer, I suspected that barrel needed a good moping with Hoppes.

[Harry Tobin]

I finally got out today after 3 days of rain & cold...it's still cold but got some sunshine to go with it.
Wasn't one of my best days but I got to compare one of Harry Tobin's Creations up against another he made that seems my favorite at the moment.



The top row was with my favorite globe...a post & globe '.385" x .110" & the notched globe is a '.353" x .110" did the bottom row.
This wasn't much of a try-out for it but already I can see that's it's 'too busy looking', sorta distracting & the lint look/diffraction was still at 12:00, in fact I think the diffraction came deeper from 12 and into that slot. I think that's what I saw.
I wasn't on my game too well today, one of those days I was glad to be done shooting.

The fresh mopped barrel put the first warmer shot over on the 11:00 side instead of the usual 3 to 6:00 area outside the target...but they got in line pretty quick after the first warmer, I suspected that barrel needed a good moping with Hoppes.

Don't ya worry old dawg, my brain has so many ideas I can't stand it!!!!