Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-14-2012, 07:50 PM   #16
Pentaxian
Just1MoreDave's Avatar

Join Date: Feb 2007
Location: Aurora, CO
Photos: Gallery | Albums
Posts: 4,858
I would expect the F35-105 to be sharper if you tested both at 55mm, making sharpness not a big concern.

The F35-105 is one of those lenses where the front element is really flat and not recessed much deeper tan the filter threads, right? I always worried about that style's potential for damage to the front glass, so a hood will help with protection. I just rummage around in my collection of hoods until I get something that works. You can experiment with a paper or cereal box tube until you find dimensions that work, then look on eBay for something close.

01-14-2012, 08:14 PM   #17
Pentaxian
JinDesu's Avatar

Join Date: Jun 2011
Location: New York City
Photos: Gallery
Posts: 5,626
You can probably find a rubber extendable hood that should work. It won't increase sharpness, but would possibly reduce CA and increase contrast (thereby making it look sharper). You can also test to see if F8 is the sharpest aperture for the lens, maybe on the longer end you should stop down to F11. And the lens may render certain things sharper based on distance - maybe it's good at closer objects than further objects (which is typical of most lenses).

You can also post process sharpness, so that can be an option.
01-14-2012, 08:32 PM   #18
Site Supporter
reivax's Avatar

Join Date: Jun 2011
Location: California
Posts: 740
Original Poster
QuoteOriginally posted by JinDesu Quote
You can probably find a rubber extendable hood that should work. It won't increase sharpness, but would possibly reduce CA and increase contrast (thereby making it look sharper). You can also test to see if F8 is the sharpest aperture for the lens, maybe on the longer end you should stop down to F11. And the lens may render certain things sharper based on distance - maybe it's good at closer objects than further objects (which is typical of most lenses).

You can also post process sharpness, so that can be an option.
The lens has threads to screw a hood on (like if I was installing a filter). Do rubber hoods have those threads? I've never used or seen a rubber hood in person. Does the material make a difference in performance? Any benefits to metal, plastic, rubber?

Edit:
I guess these are three of my best choices:
http://www.amazon.com/58mm-Metal-Standard-Screw-Mount/dp/B005UV2VJC/ref=wl_i...=2H3GBD3AQZDO2
http://www.amazon.com/EzFoto-58mm-Metal-Screw-Telephoto/dp/B0066ZFSDW/ref=wl...=2H3GBD3AQZDO2
http://www.amazon.com/gp/product/B0029Z9QIQ/ref=cm_cr_asin_lnk

I'm still curious about the benefits of different materials of hoods.

Last edited by reivax; 01-14-2012 at 08:46 PM. Reason: Answered my own question.
01-14-2012, 08:34 PM   #19
Site Supporter
reivax's Avatar

Join Date: Jun 2011
Location: California
Posts: 740
Original Poster
QuoteOriginally posted by Just1MoreDave Quote
I would expect the F35-105 to be sharper if you tested both at 55mm, making sharpness not a big concern.

The F35-105 is one of those lenses where the front element is really flat and not recessed much deeper tan the filter threads, right? I always worried about that style's potential for damage to the front glass, so a hood will help with protection. I just rummage around in my collection of hoods until I get something that works. You can experiment with a paper or cereal box tube until you find dimensions that work, then look on eBay for something close.
I really thought it would have been better at 50mm as well.

I'm assuming/hoping the lens gets a little sharper at about the 70-80 range. I know there will be a drop in sharpness around 105. All in all, I'm pretty satisfied with the lens.

01-15-2012, 02:23 AM   #20
Site Supporter
bassek's Avatar

Join Date: Feb 2011
Photos: Gallery
Posts: 577
Rubber hoods come with screw threads, you can find 3rd party rubber hoods cheap.

I have a petal hood on my F35-105. I soon found that a rotating front element does not match with a screw petal hood.
You have to zoom first, then adjust the petal hood.

BTW, my F35-105 lens is sharp. But my DAL18-55 is too at its wide end.

Seb.
01-15-2012, 03:12 AM   #21
Veteran Member
DaveHolmes's Avatar

Join Date: Jul 2010
Location: Yorkshire
Posts: 1,501
QuoteOriginally posted by JinDesu Quote
You can probably find a rubber extendable hood that should work. It won't increase sharpness, but would possibly reduce CA and increase contrast (thereby making it look sharper).
Hold on... If it 'looks' sharper, surely it 'is' sharper?

I use hoods for 3 reasons: 1)flare reduction... 2)lens protection 3)increase in contrast and sharpness...

Is reason 3 now defunct?
01-15-2012, 09:31 AM   #22
Pentaxian




Join Date: Feb 2010
Location: Eureka, CA
Photos: Gallery | Albums
Posts: 1,972
QuoteOriginally posted by bobmaxja Quote
DA L a lot sharper. Anyway color can be adjusted in PP or in camera
Perhaps at 35mm. But here you're comparing a focal range where the DA 18-55 is at its strongest with a focal range at which the 35-105 is probably weaker. At 55mm I would venture to guess that the F 35-105 is sharper, perhaps considerably sharper.

And while color can be adjusted, there are limits to what you can achieve. Nothing beats a lens with excellent, distinctive color rendition.

QuoteOriginally posted by reivax Quote
I wonder if there are any tips to increase the sharpness on the 35-105
A hood might help a little bit with the contrast. The main thing is to use a tripod, stop down the lens, and shoot in the middle of the zoom's range. Most of these older lenses are not always very sharp at the wide and long ends of the zoom. That's perhaps one of the reasons the older A version of the 35-105 is so well liked: it has more consistency across its focal range than a lot of the older zoom lenses with comparable range.

Last edited by northcoastgreg; 01-15-2012 at 09:53 AM.
01-15-2012, 09:57 AM   #23
Pentaxian
JinDesu's Avatar

Join Date: Jun 2011
Location: New York City
Photos: Gallery
Posts: 5,626
QuoteOriginally posted by DaveHolmes Quote
Hold on... If it 'looks' sharper, surely it 'is' sharper?

I use hoods for 3 reasons: 1)flare reduction... 2)lens protection 3)increase in contrast and sharpness...

Is reason 3 now defunct?
Sharpness is usually how well a lens resolves details, hence why a lot of lens testing involves resolving little lines. A loss in contrast because of stray light will cause the details to look less sharp. An increase in contrast will make the details look sharper. However, the lens can only resolve so much detail, so the maximum detail you can regain from putting on a hood is that.

01-15-2012, 10:00 AM   #24
Pentaxian
Just1MoreDave's Avatar

Join Date: Feb 2007
Location: Aurora, CO
Photos: Gallery | Albums
Posts: 4,858
QuoteOriginally posted by DaveHolmes Quote
Hold on... If it 'looks' sharper, surely it 'is' sharper?

I use hoods for 3 reasons: 1)flare reduction... 2)lens protection 3)increase in contrast and sharpness...

Is reason 3 now defunct?
Someone asked me about this when I was selling a macro lens. I tend to blab about every awful feature of the lenses I sell, and I mentioned low contrast but good sharpness. My demonstration of this:

This text is exactly

as sharp as this text

That's just reduced contrast. It may be splitting technical hairs. Also, when you get to the point of increasing sharpening in software, the extra contrast might help the software.
01-15-2012, 10:33 AM   #25
Site Supporter
reivax's Avatar

Join Date: Jun 2011
Location: California
Posts: 740
Original Poster
Just finished taking some more test shots with the 35-105 and here were some more observations I was able to make:

The lens is definitely sharper closer to 105 than it is to 35. 35mm is the weakest focal range, while somewhere between 70-90 is the strongest .

The lens takes much better pictures at 105 than I expected.

At about 70mm, f11 seems to be the ideal aperture setting for sharpness. Below 70, there is some improvement with f11, but not much of a difference, except for at 35mm. The pictures seemed sharper much sharper at f11 for 35mm. I was actually a little surprised by that. I always thought the shorter, the lower the aperture setting would need to be. There are exceptions to this, I guess?

Definitely a worthy lens. Wish it was sharper, but that would also mean a lot more expensive. For what it is, I like it. Will definitely be using it. It also gives images a different feel than the DA's do.
01-15-2012, 10:48 AM   #26
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by Just1MoreDave Quote
I would expect the F35-105 to be sharper if you tested both at 55mm, making sharpness not a big concern.

The F35-105 is one of those lenses where the front element is really flat and not recessed much deeper tan the filter threads, right? I always worried about that style's potential for damage to the front glass, so a hood will help with protection. I just rummage around in my collection of hoods until I get something that works. You can experiment with a paper or cereal box tube until you find dimensions that work, then look on eBay for something close.
Lenses with that front element design - rather exposed, not recessed much at all - like the FA50/1.4 absolutely NEED a hood to perform their best. Yes, the hood is for extra protection but, and more importantly on a day-to-day basis, it's there to eliminate stray light in order to maximize image quality. My preference for lenses like those is for the 3-stage rubber hoods that allow or multiple configurations on the lens on the fly.

01-15-2012, 10:52 AM   #27
Site Supporter
reivax's Avatar

Join Date: Jun 2011
Location: California
Posts: 740
Original Poster
QuoteOriginally posted by Docrwm Quote
Lenses with that front element design - rather exposed, not recessed much at all - like the FA50/1.4 absolutely NEED a hood to perform their best. Yes, the hood is for extra protection but, and more importantly on a day-to-day basis, it's there to eliminate stray light in order to maximize image quality. My preference for lenses like those is for the 3-stage rubber hoods that allow or multiple configurations on the lens on the fly
What about lenses like the 35-105? Is the 3 stage rubber hoods ideal for those as well?
01-15-2012, 11:23 AM   #28
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by reivax Quote
What about lenses like the 35-105? Is the 3 stage rubber hoods ideal for those as well?
That is what I was saying - IF your lens (which I do not have so I can't examine its front element placement) is like the FA50/1.4 because its front element is really far forward and not recessed at all then Yes, it really must have a hood. The 3-Stage hoods are great for zooms because their length can be adjusted to allow for wider or tele settings.
01-15-2012, 11:55 AM   #29
Site Supporter
reivax's Avatar

Join Date: Jun 2011
Location: California
Posts: 740
Original Poster
QuoteOriginally posted by Docrwm Quote
That is what I was saying - IF your lens (which I do not have so I can't examine its front element placement) is like the FA50/1.4 because its front element is really far forward and not recessed at all then Yes, it really must have a hood. The 3-Stage hoods are great for zooms because their length can be adjusted to allow for wider or tele settings.
Great. Just ordered one. Can't wait to get it to see the difference.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
approx, k-mount, lens, pentax lens, pictures, slr lens, walk-around
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax K-m/K2000 with DAL 18-55, DAL 50-200 and accessories dreamfall Sold Items 8 12-08-2011 06:07 PM
For Sale - Sold: K-x with 18-55 DAL and 50-200 DAL kit lenses leadfoot Sold Items 2 08-07-2011 08:12 AM
For Sale - Sold: Pentax K-5, DAL 21mm, DAL 40mm (US) pascal Sold Items 7 06-19-2011 11:36 PM
For Sale - Sold: DAL 18-55mm and DAL 50-300mm (US) happygui Sold Items 6 08-25-2010 01:22 PM



All times are GMT -7. The time now is 12:32 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top