Diamond .05 vs. Diamond .03 vs. Kenko .05

[Deuce 1]

OK. I'm all over Max Cohn to start importing a Diamond .05 so I can use it to replace my Kenko .05, and that way I'll have the same settings on my camera when I switch between freeflying and shooting commercial tandem video, and outside RW.

I love the .03, it is really compact, produces a bright image, and will let you see the three other fliers in linked RW. I wear my camera helmet with the .3 when I fly on my belly and on my head. It is way too wide for tandems.

So, Max lets me know he's got .5's coming in with 37mm threads to fit my PC 120 and I'm all over that as fast as you can say "Do you take Visa?"

I've attached photos, probably in two postings here of the lens on the camera, and the Kenko on my camera, and images taken with the lenses to show their field of view. The Diamond .5 is wider than the Kenko .5. We've discussed this before, here, that different manufacturers produce different fields of view. I will bump the zoom on my Diamond .5 when I shoot tandems, up to about a .6. It's no problem.

Now I can re-mount my D-box further forward on my helmet, something I didn't do with the Kenko, because I felt it presented a snag-hazard.

Another plus to the Diamond line is that they are single-element lenses. Hopefully Quade can explain this better, but on the medium to low cost range of lenses like my Kenko, the lens elements reflect off each other in light conditions where light enters from the side, and you get glare and light-ghost images in the video. I get less of this with the Diamonds, and I think it's because there are fewer lens surfaces exposed to the glare, just the Diamond and then the Zeiss lens on the Sony.

They aren't cheap, but they are competetive with the better lenses out there, and nothing is lower profile.

No, there's no threads for a filter, but a few folks at my DZ buy filters that fit over the outside of the Diamond, and gaffer tape them on.

I've decided to keep my Kenko in case my Diamond .5 gets broken, but I won't be using it any more otherwise.

That's my .02 cents.

Fly well, get video!

JP

[chachi 0]

Deauce, which exact model Kenko .5 is that one you have.

~Chachi

[mountainman 0]

I thought the Diamond .3 didn't have those black corners in them ? Does yours there in that pic ?

http://www.brandonandlaura.com

[Deuce 1]

It says SGW-05 on the outside of the lens.

Mountain man. I never noticed that before. I think that's because it's a still, not a frame-grab. It does not do that in video mode.

None of these lenses is really any good for stills, and they're all pretty poor for flash photography too. I took the stills to show relative fields of view. I hope it was helpful.

[Craig 0]

Quote

I thought the Diamond .3 didn't have those black corners in them ? Does yours there in that pic ?

I was getting ready to ask if these were frame grabs or stills since they looked alot like stills. On my PC-101 there is a difference in FOV between the two. (Stills will be a little wider).

[mountainman 0]

So, since in the photo mode, the view gets a little wider (I have a PC120, and I noticed that) and causes the minor black corners ? Hmm. However, it is still less than the .5 Kenko in still mode. I hate it since I use the stills a lot.

http://www.brandonandlaura.com

[SniperCJ 0]

Damn, when's the Diamond 0.5 with the 30mm threads coming...??

[alain 0]

>Damn, when's the Diamond 0.5 with the 30mm threads coming...??

Now: I have one on the way

Alain

[alain 0]

interesting pics Deuce !

the diamond .5 seam to have less barel distortion than your kenko.
no black corners on the diamond .5 pics.

Alain

[quade 4]

Quote

Another plus to the Diamond line is that they are single-element lenses. Hopefully Quade can explain this better, but on the medium to low cost range of lenses like my Kenko, the lens elements reflect off each other in light conditions where light enters from the side, and you get glare and light-ghost images in the video.

Ok, here we go . . .

The absolute easiest type of lens to manufacture is a lens based on a sphere. See Diagram1.

For years, this was the only type of lens that was possible to create and it's still done because, like said, it's an easy way to make a lens. The lens can be made by a fairly simple machine.

The problem with a spherical lens is that different wavelenghts of light will focus at different distances. See Diagram2. This is known as chromatic blur. For highly critical work like astronomical telescopes or high quality photography, this means that the image will be slightly blurred and out of focus.

In an attempt to correct for this, manufacturers can add additional lens elements made of different glass with a different index of refraction. See Diagram3 (stolen from UCLA, 'cause like, hey, I'm too lazy to make another drawing).

This introduces its' own issues of ghost images and lens flare. Coatings help, but they're not perfect.

The absolute ideal lens would probably be a single element ashperic lens (obviously made under computer machine control), but it would be incredibly difficult (impossible actually) to get something like that to both focus AND zoom.

quade -
The World's Most Boring Skydiver

[LouDiamond 1]

Quote

I've decided to keep my Kenko in case my Diamond .5 gets broken, but I won't be using it any more otherwise.

BASTARD, you said you would sell it to me when you got yoour diamond in. I see how you is now

BTW, got back from TDY and the video looks good, nice porno music. I have a music prog for ya, if interested PM me

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[alain 0]

cool post (again, thanks)

little question: is chromatic blur more sensitive on long focal lenses (ie 200mm vs 20mm) ?

Alain

[nacmacfeegle 0]

"I thought the Diamond .3 didn't have those black corners in them ? Does yours there in that pic "

I think this is called vignetting, you probably won't see it on a normal TV set with the diamond 0.3. If youdo, a small amount of 'zoom in' will get rid of this unwanted effect.
Not everything the camera records is replayed on a TV set, if you have Premiere, check out the "title safe" areas to see how much image is actualy lost.

--------------------

He who receives an idea from me, receives instruction himself without lessening mine; as he who lights his taper at mine, receives light without darkening me. Thomas Jefferson

[quade 4]

Quote

little question: is chromatic blur more sensitive on long focal lenses (ie 200mm vs 20mm) ?

Absolutely!

Which is why I think these wide angle lenses can get away with being made so, uh, inexpensively -- that and they're being used for video, which is pretty crappy resolution to begin with (compared to film).

quade -
The World's Most Boring Skydiver

[Deuce 1]

Thanks much, Q.

JP

[freakydiver 0]

Dumb question - where is the best place to go about purchasing 30mm Diamond lenses?

Thank you all in advance.

-- (N.DG) "If all else fails – at least try and look under control." --

[Deuce 1]

http://www.generationfreefly.com/diamond.3/

Tell him to send JP a T-shirt!

[quade 4]

Update.

Their new web site.

quade -
The World's Most Boring Skydiver

[Deuce 1]

The site doesn't mention the .5, but Max has it. It's dynamite for tandems and RW. If you look further up the post, you'll see the comparison pictures I took. No, the vignette does not show on the video.

[skydiverjon 0]

I just ordered the .05, but Max called it the stealth .5x....lol

[freakydiver 0]

Deuce - having saved up some dough to start bolstering my video lens collection I just wanted to say a big thanks for your information - it is a large help!

-- (N.DG) "If all else fails – at least try and look under control." --