[CarlJF]

I've recently tried to use the blur control on my Q (original one) for some casual portraits and the results are somewhat puzzling. The only thing this seems to do, even on the lowest setting, is to blur the whole image. Even the part where the focus was set on gets blurred, which is not exactly the desired result...

So, I'm just wondering if there are some tricks I need to know to make BC works as it should ? Or this feature is just too buggy to be useful ?

[mattt]

My findings are similar to yours.....


Posting to subscribe to this thread to see If I can find a tip or two out myself.

[blackcloudbrew]

Which lens are you using?

[CarlJF]

Which lens are you using?

I usually use the 01. But I also sometimes use the 06 and the results aren't any better.

[UncleVanya]

I do not have a Q but I read about this and found the original source.

Pentax Q Review - Depth of Field and Blur Control | PentaxForums.com Reviews

Note that they say you should be using a tripod and that the results are not very good compared to traditional methods on normal cameras of controlling depth of field. I think you will have to resort to post processing to really do this correctly. Also I think the fact that blur control only works on JPG files limits the usefulness a bit.

[CarlJF]

I do not have a Q but I read about this and found the original source.

Pentax Q Review - Depth of Field and Blur Control | PentaxForums.com Reviews

Note that they say you should be using a tripod and that the results are not very good compared to traditional methods on normal cameras of controlling depth of field. I think you will have to resort to post processing to really do this correctly. Also I think the fact that blur control only works on JPG files limits the usefulness a bit.

Ouch! Needing a tripod kind of make the blur control useless. When I'm willing to carry a tripod, I also usually don't mind to carry my DSLR!
Blur control only applies to JPG but you can still save the RAW to reprocess the shot as a normal JPG. So, at least, you don't lose much by trying BC. The only limitation then becomes that the shot will be done at maximum aperture.

[patarok]

buy the original K-mount adapter and a 40mm XS... bokeh and shallow DoF "en masse"...

no offense here, but:
there are a lot of mini tripods that will fit into a breast/shirt pocket...bean or rice bags also do the trick sometimes. But as i said, use either an adapter with a cool lens on or buy old video lenses and an according adapter.. I like the results

and, talking about the BC function:
as it only "computes" DoF it will have problems when the algorithm "recognizes" a multitude of objects at the same focus plane and multiple objects with nearly the same geometry in front and behind the object you are focusing at.

conclusion regarding the issue:
I guess it only works acceptable if the main object you are focusing on heavily contrasts with the backround in size, geometry and somehow in color(and or texture if you wish so...)

[reh321]

I've recently tried to use the blur control on my Q (original one) for some casual portraits and the results are somewhat puzzling. The only thing this seems to do, even on the lowest setting, is to blur the whole image. Even the part where the focus was set on gets blurred, which is not exactly the desired result...

So, I'm just wondering if there are some tricks I need to know to make BC works as it should ? Or this feature is just too buggy to be useful ?

The answer may be to find a lens that provides bokeh on its own.

Suleeto has posted pictures taken with a c-mount lens that seems to go from shallow DoF to deep DoF on a Q, depending on aperture
https://www.pentaxforums.com/forums/136-pentax-q/308107-got-my-c-q-adapter-cctv-lens.html

[pacerr]

By definition, the effect is to Blur the entire image. If you're wanting to de-sharpen a given area within the image (especially by a varying amount) you'll need to use post processing software that can selectively target and shape the area for that effect.

Without the means to manually select and size the target area a camera preset would often miss the target unless you were constrained to a specific location in the VF which is not a very satisfying effect.

[UncleVanya]

By definition, the effect is to Blur the entire image. If you're wanting to de-sharpen a given area within the image (especially by a varying amount) you'll need to use post processing software that can selectively target and shape the area for that effect.

Without the means to manually select and size the target area a camera preset would often miss the target unless you were constrained to a specific location in the VF which is not a very satisfying effect.

I'm not sure what you mean "by definition...' the intent from Pentax was to detect the area you focused on and blur the background. However in testing the results are mostly hit or miss and work better with centered subjects.

Pentax Q Review - Depth of Field and Blur Control | PentaxForums.com Reviews

[pacerr]

I'm not sure what you mean "by definition...' the intent from Pentax was to detect the area you focused on and blur the background.

Poor phrasing on my part. I'd meant to include 'around the area of sharpest focus'. I'm still uncertain what criteria is used to define that area since it seems to only be available with AF lenses and depends on precise AF.

The inability to pre-visualize the area of blur in the VF as a vignette seems critically limiting to me and favors applying the effect in PP.

[UncleVanya]

Poor phrasing on my part. I'd meant to include 'around the area of sharpest focus'. I'm still uncertain what criteria is used to define that area since it seems to only be available with AF lenses and depends on precise AF.

The inability to pre-visualize the area of blur in the VF as a vignette seems critically limiting to me and favors applying the effect in PP.

That makes sense. Thanks for clarifying.

[CarlJF]

As an update to this thread, I have upgraded my Q for a Q7. BC works a lot better on this last one, particularly on shots where the background and subject are already well separated. It seems that the processing engine has been improved and does a better job at identifying which part of the image should stay sharp and which ones has to be blurred. Sure, it's not a 100% keeper rate, but it's good enough that I consider using the feature on a casual basis. I always save the raw file anyway so that if the result is ugly it's still possible to process the picture without BC or by adding it in PP.

So far, on the Q7 I would say that the "low" setting works more often than not, the "medium" one is a hit and miss but looks really good when it works, and the high setting ususally looks ugly and artificial. For now, I will mostly stick with the low setting for a safe shot and do more experiment with the medium to better determine under which situations it works best.

[Stone G.]

My experiences with the Q10 is that BC works provided that the camera is kept rock steady. It seems as if there is no auto-alignment of the two exposures needed to produce the BC image and that you need to have the focus point placed at exactly the same spot during these two exposures.


Whether you find the effect useful/acceptable or not is a matter of taste, but I think the 'low' setting may find its use in still-life photography with the Q(s).


I also agree with CarlJF that the 'high' setting is really a bit too much:










Addendum: Images were taken with the Pentax 02 Standard Zoom on the Q10.

[CarlJF]

Stone G., your results looks similar to what I got with my Q7. They're much better than what I see with my original Q. Since the Q and Q10 are the same camera in a different body, I'm almost wondering if my Q could be defective. I don't have time this evening, but tomorrow I will post an example of what I get with my Q...