Front Element Condition

On Thu, 27 Nov 2008 23:47:13 -0800, Paul Furman wrote:

Blinky the Shark wrote:
Paul Furman wrote:

Blinky the Shark wrote:
I ran across this demonstration (three images) the other day. It's pretty
good. And succinct.

http://www.lensrentals.com/news/2008...ment-scratches
Just a tiny bit of damage for that one ;-)

The only time you will obviously notice front scratches and interior
dust is in a situation like this:
http://edgehill.net/Misc/photography...6-28-07/pg1pc5
-where different optical principles apply... note the repeating dust
patterns in each circle, slightly offset.

Good example. And in the one with the leaves in the foreground.

Speaking of bokeh, here's the only test for which I've actually assembled
the results:

http://www.pbase.com/blinkytheshark/image/104408541

Nice soft edges. There is a bit of a bright ring. Supposedly Nikons tend
to have a crisp line and even illumination on the OOF circles, the soft
edge is a clear difference between yours & my examples though taken a
much different focal lengths, distances & lighting contrast. I pretty
much gave up on the bokeh tests though: with a reasonable lens there is
lots of play in the way you set it up & what lighting makes a nice look,
even lenses famous for their soft bokeh can be made to look bad & some
bad lenses can produce nice smooth OOF with care. The slight ring I saw
could be some limited effect for those particular conditions. I would
like to have something that consistently gave a softer edge like those
Tamron samples but the fact is among comparable lenses I can't tell the
difference unless the two sat on the same tripod location.

Speaking of supposedly famous bokeh lenses, mostly I think they are just
nice fast lenses, like 85/1.4 or 135/2 or any macro lens which at close
range produces a lot of OOF in the background. There are bad bokeh
lenses too but it's rare that you can't make those look good. I've got a
Nikon 50mm f/1.2 which is really a pretty bad bokeh lens by it's
reputation... it can be made to look really really freaky bad but
nonetheless it does put out a lot of OOF and with some attention, it's
not hard at all to make beautiful soft buttery bokeh art with it.

Let us all bow down and now worship the blurriness of DSLR glass.

LOL

Blinky the Shark wrote:
[]
Please ignore my last two posts to this thread; I didn't notice I was
responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
useful contributors to the group: sorry about that; it just makes more
noise.

You're forgiven, Blinky! Next it will be claiming that its small-lens
camera can produce identical bokeh....

A useful and interesting series of images - thanks for posting them.

David

Mark Thomas wrote:

By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
leaving it there?, because I might bookmark it for later use - I
sometimes get asked and that's a nice way to show the concept, and a
good lens example..

Interestingly I've only ever had one Tamron lens where I took any notice
of the bokeh, and that was a 70-150 f3.5 zoom. Not exactly a high end
lens, but geez it was a superb portrait lens, and it really did have
lovely oof effects. I wonder if it was deliberate design or just a
lucky coincidence..

I have an old 75-150mm f/3.5 Nikon Series E which is probably the same
exact lens. Nikon didn't make them and they were marketed as an bargain
line but it gained a good reputation. Nice compact mf push-pull zoom and
pretty fast specs for the size. It doesn't seem to get super sharp but
has good local contrast.

And also has dust in it:
http://edgehill.net/California/Bay-A...ll-set/pg3pc12
:-)
not bad with a +2 diopter Canon 300D 2-element closeup lens:
http://edgehill.net/California/Bay-A.../plants/9-4-07

--
Paul Furman
www.edgehill.net
www.baynatives.com

all google groups messages filtered due to spam

On Fri, 28 Nov 2008 07:56:39 GMT, "David J Taylor"
wrote:

Blinky the Shark wrote:
[]
Please ignore my last two posts to this thread; I didn't notice I was
responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
useful contributors to the group: sorry about that; it just makes more
noise.

You're forgiven, Blinky! Next it will be claiming that its small-lens
camera can produce identical bokeh....

A useful and interesting series of images - thanks for posting them.

David

Actually, it can do even better than that. I was quite surprised that the bokeh
in that f/5.6 image was as minor as it was. When using the proper achromat
close-up lens on a P&S camera at f/2.0, a point of light 20 inches away would
have disappeared beyond the bounds of the image frame. (Not to mention it would
have pixel-sharp edges and details on the in-focus LED.) Note that's even 3
stops wider than you had available in your $380 lens. (What did it cost new when
you bought it, $500? I quoted the year-old prices online today. Nevermind, I
found an original price quoted online, $450. And that's from a discount supplier
known for their low-low prices. LOL.)

Flash wouldn't have been needed at all with my P&S cameras at f/2.0, being able
to even better demonstrate what you hoped to display.

You all really are perfect fools, aren't you.

This is abso****alutely amazing.

LOL!!

Go ahead, turn tails and praise the soft-edges and blurriness in dedicated DSLR
glass again. I'm getting quite a laugh out of this. LOL Mind if I use your LED
photo as comparison against those P&S SX10 samples? Then we can claim an over
50x's more resolution on the P&S lens compared to dedicated DSLR glass instead
of just 10x's more resolution from the P&S 20x zoom PLUS macro lens. LOL

Paul Furman wrote:
Mark Thomas wrote:

By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
leaving it there?, because I might bookmark it for later use - I
sometimes get asked and that's a nice way to show the concept, and a
good lens example..

Interestingly I've only ever had one Tamron lens where I took any
notice of the bokeh, and that was a 70-150 f3.5 zoom. Not exactly a
high end lens, but geez it was a superb portrait lens, and it really
did have lovely oof effects. I wonder if it was deliberate design or
just a lucky coincidence..

I have an old 75-150mm f/3.5 Nikon Series E which is probably the same
exact lens. Nikon didn't make them and they were marketed as an bargain
line but it gained a good reputation. Nice compact mf push-pull zoom and
pretty fast specs for the size. It doesn't seem to get super sharp but
has good local contrast.

And also has dust in it:
http://edgehill.net/California/Bay-A...ll-set/pg3pc12

Saw those before - very cool!

not bad with a +2 diopter Canon 300D 2-element closeup lens:
http://edgehill.net/California/Bay-A.../plants/9-4-07

That's a lovely series. I nearly fell asleep as I was becalmed..

It could well be the same (optically, anyway) lens - mine is a two ring
version, *but* I'm pretty sure both push-pull and twin versions were
available at the time (remember the good old days when there was a good
choice of oem lenses...?) - I liked the feel (and look.. - I'm shallow)
of the two ring version better.

I'm also pretty certain both the Vivitar and Tokina 'equivalent'
competitors were f3.8, so I doubt if they made the 'Nikon'. I think at
the time I knew who made whose budget lenses, but I've long forgotten now.

As an aside, about 4 years after I bought the Tamron, the focus became a
little erratic, and I noticed the scary rattle of a loose internal
element. As I have a little mechanical nouse, I very bravely laid the
lens on a very large white sheet (to catch any flying springs..) and
proceeded to pull it to bits. The element was quite deep inside, but I
eventually got there and managed to successfully put it all back
together. It's currently with a friend, and is still going strong.
*Beautifully* built, unlike another Tamron I had from that era..

On Thu, 27 Nov 2008 19:59:23 -0800, Blinky the Shark
wrote:

Paul Furman wrote:

Blinky the Shark wrote:
I ran across this demonstration (three images) the other day. It's pretty
good. And succinct.

http://www.lensrentals.com/news/2008...ment-scratches

Just a tiny bit of damage for that one ;-)

The only time you will obviously notice front scratches and interior
dust is in a situation like this:
http://edgehill.net/Misc/photography...6-28-07/pg1pc5
-where different optical principles apply... note the repeating dust
patterns in each circle, slightly offset.

Good example. And in the one with the leaves in the foreground.

Speaking of bokeh, here's the only test for which I've actually assembled
the results:

http://www.pbase.com/blinkytheshark/image/104408541

That's not such a great test of bokeh for comparing different lenses
because just about any, even those with bad bokeh, will look about the
same using that setup. What you need is something in the background
that has strong highlights, small sources of light, like maybe the sun
glinting off dew on leaves, reflections of a bulb in curved chrome,
whatever. Tough tests like that will really reveal the differences in
bokeh between different lenses.

Steve

Gabe McDonnel wrote:
On Wed, 26 Nov 2008 15:06:47 -0800, Blinky the Shark
wrote:

I ran across this demonstration (three images) the other day. It's pretty
good. And succinct.

http://www.lensrentals.com/news/2008...ment-scratches

In astronomy it's not uncommon to fix a mirror that has a bad scratch or chip by
covering it over or filling it in with flat-black pigment. The images are again
good as new. There is one famous case of a large diameter research telescope
mirror that was shot at a few times with a gun (disgruntled employee, if I
recall), causing huge chinks and conchoidal fractures in it. They filled in the
large holes, painted them black, and the telescope still had most of its
original quality. As long as the lenses' curvatures hold their integrity, you
can get by with quite a bit of defects.

snip
That was at the MacDonald Observatory in the Davis Mountains in the Big
Bend area of Texas. The biggest problem they have now is not bullet
holes, but smog from Mexican factories. When it was built in 1935 or
thereabouts, the atmosphere out there was crystal clear about 355 days
per year, but, alas, no more. Incidentally, that scope (82 inch
diameter) is no longer their primary instrument but it is still quite
useful.
Allen

Mark Thomas wrote:

Blinky the Shark wrote:
Blinky the Shark wrote:

BlackyMason wrote:

Since you insist ... lots of noise on that sensor too. What kind of
camera was it?
D60

Were you having to use high ISO because you couldn't use flash for
macro on luminous objects?
ISO 400

Please ignore my last two posts to this thread; I didn't notice I was
responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
useful contributors to the group: sorry about that; it just makes more
noise.


That's ok - if he posts sensibly, why not. But you could see where he
was going with that one.. (O:

By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
leaving it there?, because I might bookmark it for later use - I
sometimes get asked and that's a nice way to show the concept, and a
good lens example..

Yes, it'll be there, Mark; I didn't just put it up for this discussion. I
did it for me last summer, then wanted something orderly to share with a
friend, so I made that composite. Just last night I was trying to figure
out what software I used to create that composite, and I'm damned if I
could figure it out.


--
Blinky
Killing all posts from Google Groups
The Usenet Improvement Project: http://improve-usenet.org
Need a new news feed? http://blinkynet.net/comp/newfeed.html

Mark Thomas wrote:

Blinky the Shark wrote:
Blinky the Shark wrote:

BlackyMason wrote:

Since you insist ... lots of noise on that sensor too. What kind of camera was
it?
D60

Were you having to use high ISO because you couldn't use flash for macro
on luminous objects?
ISO 400

Please ignore my last two posts to this thread; I didn't notice I was
responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
useful contributors to the group: sorry about that; it just makes more
noise.


That's ok - if he posts sensibly, why not. But you could see where he
was going with that one.. (O:

By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
leaving it there?, because I might bookmark it for later use - I
sometimes get asked and that's a nice way to show the concept, and a
good lens example..

Interestingly I've only ever had one Tamron lens where I took any notice
of the bokeh, and that was a 70-150 f3.5 zoom. Not exactly a high end
lens, but geez it was a superb portrait lens, and it really did have
lovely oof effects. I wonder if it was deliberate design or just a
lucky coincidence..

That was a big part of my decision to buy the Tamron. I spent a lot of
time looking at bokeh shots online before getting it (after renting one
for a week). The one I bought, back when the Tamron 90 2.8 was
back-ordered *everywhere*, was the very one I had rented from
LensRentals.com, when it came up for sale a month or two later (they sell
them after x months in the rental inventory).


--
Blinky
Killing all posts from Google Groups
The Usenet Improvement Project: http://improve-usenet.org
Need a new news feed? http://blinkynet.net/comp/newfeed.html

Paul Furman wrote:

Speaking of supposedly famous bokeh lenses, mostly I think they are just
nice fast lenses, like 85/1.4 or 135/2 or any macro lens which at close
range produces a lot of OOF in the background. There are bad bokeh
lenses too but it's rare that you can't make those look good. I've got a
Nikon 50mm f/1.2 which is really a pretty bad bokeh lens by it's
reputation... it can be made to look really really freaky bad but
nonetheless it does put out a lot of OOF and with some attention, it's
not hard at all to make beautiful soft buttery bokeh art with it.

More bokeh, from my bookmarks:

http://www.pbase.com/miljenko/ccrm_bokeh_tests

And note the composite image for direct comparison.


--
Blinky
Killing all posts from Google Groups
The Usenet Improvement Project: http://improve-usenet.org
Need a new news feed? http://blinkynet.net/comp/newfeed.html