Jump to content

Recommended Posts

I bought my wife the little Sony RX100 Mk1 some time ago having heard good reports and thought I might borrow it occasionally for unobtrusive stock. ;) However having used it just a few times I've been a little disappointed that sharpness anywhere except the centre circular third is not as good as I'd hoped. Admittedly I'm not fully conversant with all the camera functions, so my question really is what are your experiences with the Mk1 and what settings do you find work best? So far I've only submitted one or two images to Alamy that I was sure wouldn't fail QC.

Edited by Sultanpepa
Link to post
Share on other sites

Hi

I have submitted lots of images from my Rx100, and passed QC, but the vast majority have been down sized to improve sharpness.

Yes, I think I did that with the few I submitted.

Link to post
Share on other sites

There have been reports on decentered lenses. It's not difficult to do a test: take an image of a double newspaper page with small print at every stop for the main focal lengths. Be sure to have the camera and the newspaper lined up square.

 

The quickest way: first take two mirror tiles. (Mine are from Ikea.) Scrape off the silver layer on the back of one of them using a sharp hobby knife or scalpel blade. A circle about 7 to10 mm exactly in the middle is best. (A rough hole will do, but a circle that's a bit nicer works slightly easier as it is quicker to determine where to hold it in relation to the lens.

 

Put the camera on a tripod. Take a piece of string or a tape ruler and hang the double page on the wall with the middle at exactly the height of the middle of the lens. Mark that middle point. Aim the camera at the newspaper only by shifting the tripod until the newspaper and camera are more or less squared up and the newspaper fills the entire viewfinder screen.

 

Place the mirror without a hole precisely flush with the wall in the middle of the newspaper. Hold the tile with the scraped hole in front of the lens with the mirror side facing the wall. Hold the tile perfectly flat to the front of the lens. With larger cameras I use 2 rubber bands, but those may damage or at least hamper the fragile focusing mechanism of the RX100.

Aim at the mirror on the wall and initially shift the tripod until you see a sort of tunnel in the viewfinder / on the screen. It should be centered.

If the tunnel veers up or down, now adjust the ballhead up or down. If the setup is perfect, the hole through which the lens is looking at the mirror on the wall, will disappear in the center of a dark sort of tube of reflections of that hole. It's far easier to do than it sounds and pretty intuitive when you're doing it.

 

Now with the camera on A -aperture priority- cycle through all apertures. Repeat for both extremes and two or three average focal lengths. Shift the tripod so that the newspaper fills the viewfinder screen every time. If the place of the paper in the finder is the same, it is easier to judge sharpness for different focal lengths relative to each other.

 

In general you will expect the highest sharpness at around f4 and the greatest evenness of sharpness around 5.6 or 8.  So there's your first  physical problem.

 

Even lighting helps in judging: use two identical lights on either side of the double page, but aim them at the opposite [side of the] page. Use a full length pencil to determine the evenness of the lighting. Put the point of the pencil in the middle and hold the pencil perpendicular to the wall. Shift the lamps until the shadows are of equal length and density. With more than 2 light sources: all shades must be equal. If you happen to have a shiny paper, keep lamps closer to the wall than to the camera. (=at an angle sharper than 45 degrees to the subject.)  If there is great unevenness, pull the lamps further away from the subject.

 

This is a basic and fail safe repro setup. And is perfectly suited for testing sharpness and evenness of lenses.

With the two mirrors as a tool it's only a couple of minutes to set up.

 

wim

  • Upvote 3
Link to post
Share on other sites

Yes, some edge softness, but I always downsize to 3600 or 4000px on the long side, and have had no QC problems yet

I haven't failed QC yet with any camera but edge softness on the RX100 at full size must be touch and go. Alamy approve the camera so I wonder if this edge softness is taken into account by QC?

 

There have been reports on decentered lenses. It's not difficult to do a test: take an image of a double newspaper page with small print at every stop for the main focal lengths. Be sure to have the camera and the newspaper lined up square.

 

The quickest way: first take two mirror tiles. (Mine are from Ikea.) Scrape off the silver layer on the back of one of them using a sharp hobby knife or scalpel blade. A circle about 7 to10 mm exactly in the middle is best. (A rough hole will do, but a circle that's a bit nicer works slightly easier as it is quicker to determine where to hold it in relation to the lens.

 

Put the camera on a tripod. Take a piece of string or a tape ruler and hang the double page on the wall with the middle at exactly the height of the middle of the lens. Mark that middle point. Aim the camera at the newspaper only by shifting the tripod until the newspaper and camera are more or less squared up and the newspaper fills the entire viewfinder screen.

 

Place the mirror without a hole precisely flush with the wall in the middle of the newspaper. Hold the tile with the scraped hole in front of the lens with the mirror side facing the wall. Hold the tile perfectly flat to the front of the lens. With larger cameras I use 2 rubber bands, but those may damage or at least hamper the fragile focusing mechanism of the RX100.

Aim at the mirror on the wall and initially shift the tripod until you see a sort of tunnel in the viewfinder / on the screen. It should be centered.

If the tunnel veers up or down, now adjust the ballhead up or down. If the setup is perfect, the hole through which the lens is looking at the mirror on the wall, will disappear in the center of a dark sort of tube of reflections of that hole. It's far easier to do than it sounds and pretty intuitive when you're doing it.

 

Now with the camera on A -aperture priority- cycle through all apertures. Repeat for both extremes and two or three average focal lengths. Shift the tripod so that the newspaper fills the viewfinder screen every time. If the place of the paper in the finder is the same, it is easier to judge sharpness for different focal lengths relative to each other.

 

In general you will expect the highest sharpness at around f4 and the greatest evenness of sharpness around 5.6 or 8.  So there's your first  physical problem.

 

Even lighting helps in judging: use two identical lights on either side of the double page, but aim them at the opposite [side of the] page. Use a full length pencil to determine the evenness of the lighting. Put the point of the pencil in the middle and hold the pencil perpendicular to the wall. Shift the lamps until the shadows are of equal length and density. With more than 2 light sources: all shades must be equal. If you happen to have a shiny paper, keep lamps closer to the wall than to the camera. (=at an angle sharper than 45 degrees to the subject.)  If there is great unevenness, pull the lamps further away from the subject.

 

This is a basic and fail safe repro setup. And is perfectly suited for testing sharpness and evenness of lenses.

With the two mirrors as a tool it's only a couple of minutes to set up.

 

wim

Hi Wim, I don't think it's a de-centred lens but more just that I'm used to results from a D610. However I still think I could squeeze better performance from it if I knew my way around it better. I will almost certainly downsize images but wondered what preferential settings more experienced users were using.  That's an intricate set-up you've described there. I'll maybe give it a try once I get hold of some mirrors.

Edited by Sultanpepa
Link to post
Share on other sites

Hi Wim, I don't think it's a de-centred lens but more just that I'm used to results from a D610. However I still think I could squeeze better performance from it if I knew my way around it better. I will almost certainly downsize images but wondered what preferential settings more experienced users were using.  That's an intricate set-up you've described there. I'll maybe give it a try once I get hold of some mirrors.

 

Sorry, a bit brief:

The thing is: if it is  a decentered lens, you can claim a new one.

If the lens is good, or at least within specs, a brief test will show which apertures you think are acceptable.

 

wim

Link to post
Share on other sites

I submitted 100s of images from my Mk1 RX100 without failure.  The edges can be a tad soft but not enough to fail QC - as long as the main subject is pin sharp.  

 

I found the 'sweet spot' on that lens was f5.6.   If you look at my portfolio you will see page after page of images all taken with the RX100 Mk1.  I only have one camera - DSLR all sold.  The RX100 covers all my stock needs but won;t suit everyone.

 

I now have an RX100 Mk3 - the new lens is noticeably sharper at the edges.

 

My main reasons for changing to the Mk3 -

 

Improved lens

Electronic Viewfinder

Able to fix Aperture and Shutter leaving ISO as the auto mode.

Tiltable rear viewfinder screen

 

Regards

John

Link to post
Share on other sites

 

Hi Wim, I don't think it's a de-centred lens but more just that I'm used to results from a D610. However I still think I could squeeze better performance from it if I knew my way around it better. I will almost certainly downsize images but wondered what preferential settings more experienced users were using.  That's an intricate set-up you've described there. I'll maybe give it a try once I get hold of some mirrors.

 

Sorry, a bit brief:

The thing is: if it is  a decentered lens, you can claim a new one.

If the lens is good, or at least within specs, a brief test will show which apertures you think are acceptable.

 

wim

 

Thanks Wim, good to know

 

I submitted 100s of images from my Mk1 RX100 without failure.  The edges can be a tad soft but not enough to fail QC - as long as the main subject is pin sharp.  

 

I found the 'sweet spot' on that lens was f5.6.   If you look at my portfolio you will see page after page of images all taken with the RX100 Mk1.  I only have one camera - DSLR all sold.  The RX100 covers all my stock needs but won;t suit everyone.

 

I now have an RX100 Mk3 - the new lens is noticeably sharper at the edges.

 

My main reasons for changing to the Mk3 -

 

Improved lens

Electronic Viewfinder

Able to fix Aperture and Shutter leaving ISO as the auto mode.

Tiltable rear viewfinder screen

 

Regards

John

Thanks John, I steal it from my wife and have a play at 5.6  :ph34r:  ;)

  • Upvote 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.