[Gooshin]

could someone explain to me why viewfinders have less than 100% viewing areas

is this an engineering constraint where you need to create a base for the viewfinder to sit in, or something mythical all together?

[stevebrot]

Excellent question Gooshin. I have often wondered the same thing. I have owned 3 SLRs and none has provided 100% viewfinder coverage. The 95% claimed for my K10D sounds pretty good until you compare the actual images to what was originally framed. That last 5% is HUGE!

Steve

[Kirivon]

Cameras with 100% coverage viewfinders do exist. The A900, D3/300, 1DsMK3, and E-3 all have them. These cameras, however, are marketed as pro level equipment. If I had to guess, the thinking is probably something like this: amateurs and prosumers won't notice the 5% coverage disparity as much as they will the increased price. And, for those who want 100% out of their gear, they can pony up the scratch for the top of the line models.

The entry and mid level camera markets are all about features versus cost. I remember watching a video on how lenses are made that mentions that a kilogram of optical glass can cost up to a thousand dollars. So theoretically by cutting a couple of grams of glass and saving a couple of dollars per camera, they can put that money towards something more marketable. Say, for example, to offset R&D costs for a higher megapixel sensor.

Of course this is all conjecture but, 95% viewfinders are de-facto in entry level and prosumer equipment, so why spend more money to make something better when you don't have to?

That isn't to say I wouldn't love 100% coverage, though. It's annoying when you're trying to carefully crop something out of the frame, only to look down at your LCD later to find it still there. And, while they're at it, they can get rid of the useless pop-up flash to try and balance out the extra cost. I know that won't happen as I'm sure there are people who will never buy an off-camera flash, and therefore rely on the built in unit, but I can dream right?

[Gooshin]

Cameras with 100% coverage viewfinders do exist. The A900, D3/300, 1DsMK3, and E-3 all have them. These cameras, however, are marketed as pro level equipment. If I had to guess, the thinking is probably something like this: amateurs and prosumers won't notice the 5% coverage disparity as much as they will the increased price. And, for those who want 100% out of their gear, they can pony up the scratch for the top of the line models.

The entry and mid level camera markets is all about features versus cost. I remember watching a video on how lenses are made that mentions that a kilogram of optical glass can cost up to a thousand dollars. So theoretically by cutting a couple of grams of glass and saving a couple of dollars per camera, they can put that money towards something more marketable. Say, for example, to offset R&D costs for a higher megapixel sensor.

Of course this is all conjecture but, 95% viewfinders are de-facto in entry level and prosumer equipment, so why spend more money to make something better when you don't have to?

That isn't to say I wouldn't love 100% coverage, though. It's annoying when you're trying to carefully crop something out of the frame, only to look down at your LCD later to find it still there. And, while they're at it, they can get rid of the useless pop-up flash to try and balance out the extra cost. I know that won't happen as I'm sure there are people who will never buy an off-camera flash, and therefore rely on the built in unit, but I can dream right?

thank you, but you missed my question entirely, which is "what are the design/engineering reasons and or problems/limitations"

[Kirivon]

thank you, but you missed my question entirely, which is "what are the design/engineering reasons and or problems/limitations"

Oh. Yes, I missed that.

In my mind I had mistakenly construed the sole design/engineering constraint of 100% finders down to being an issue of physical dimensions, which therefore led me to the issue of cost.

If we're talking strictly engineering/design limitations of having 100% coverage, however, there is the issue of magnification. The higher the coverage, the lower the possible magnification, and vise versa.

Having higher magnification means that the actual viewing area of the finder will be larger. So, while a shiny 6k 1DsMk3 will show me 100% of the frame, my 60 dollar 0.88x magnification K1000 will blow it out of the water as far as perceived viewfinder size is concerned.

Hopefully this post is more relevant to your question than my last one.

[Gooshin]

why does magnification suffer on account of viewing area?

[Kirivon]

why does magnification suffer on account of viewing area?

Understanding Viewfinders


"Ironically, magnification for 100% finders has to be made lower so that viewfinder information displays can fit in the finder and be within the user's field of view. "

[ManuH]

could someone explain to me why viewfinders have less than 100% viewing areas

is this an engineering constraint where you need to create a base for the viewfinder to sit in, or something mythical all together?

I remember reading that the build tolerances for a 100% viewfinder had to be much tighter hence the cost hence this feature is often reserved on more expensive "pro" cameras.

[Wheatfield]

could someone explain to me why viewfinders have less than 100% viewing areas

is this an engineering constraint where you need to create a base for the viewfinder to sit in, or something mythical all together?

It allows for some variance during assembly of the camera. Back in the early 70s when I was looking at buying a Nikon F2s, the Nikon rep told me that a significant portion of the cost of an F2 was shimming the viewfinder to the camera so that the 100% viewfinder was 100% accurate as well. Apparently the finders were factory matched to the cameras, and should not be interchanged between cameras.
There are all sorts of myths surrounding this topic. The old wives tale was so that viewfinders would more closely match slides, which are slightly cropped by the mount. Then it morphed into the viewfinder matching the cropping that negatives received during printing.

Non of it is true. it's purely a $$ issue. 1K$ K20D would probably cost more like 1500.00 if they gave it a 100% viewfinder.

[Kirivon]

It allows for some variance during assembly of the camera. Back in the early 70s when I was looking at buying a Nikon F2s, the Nikon rep told me that a significant portion of the cost of an F2 was shimming the viewfinder to the camera so that the 100% viewfinder was 100% accurate as well. Apparently the finders were factory matched to the cameras, and should not be interchanged between cameras.

Given the slanted viewfinder issues with the K10D, this makes a lot of sense.

[Big Dave]

Gooshin,
Nikon introduced the Nikon F in 1959 with a 100% finder. It required a larger mirror and mirror box. The mechanism had to be well engineered for motor drive operation also. A condensor lens is used above the focusing screen to reduce light fall off in the corners. So, a smaller finder needs a smaller mirror etc. We get higher frame rates on a cheaper design. The body can also be made smaller and lighter. This is the path for most camera makers, which increases profits. Most users don't notice the size difference, until they do work on a copystand. Then they notice the border on the output. What I have always hated is the different aspect ratio of the classic 35mm format, compared to the paper aspect ratios.

Dave

could someone explain to me why viewfinders have less than 100% viewing areas

is this an engineering constraint where you need to create a base for the viewfinder to sit in, or something mythical all together?

[borno]

It allows for some variance during assembly of the camera. Back in the early 70s when I was looking at buying a Nikon F2s, the Nikon rep told me that a significant portion of the cost of an F2 was shimming the viewfinder to the camera so that the 100% viewfinder was 100% accurate as well. Apparently the finders were factory matched to the cameras, and should not be interchanged between cameras.
There are all sorts of myths surrounding this topic. The old wives tale was so that viewfinders would more closely match slides, which are slightly cropped by the mount. Then it morphed into the viewfinder matching the cropping that negatives received during printing.

Non of it is true. it's purely a $$ issue. 1K$ K20D would probably cost more like 1500.00 if they gave it a 100% viewfinder.

Yeah I remember the one about slide coverage, somebody in marketing must have used it as a good excuse for the less coverage.

[axl]

Excellent question Gooshin. I have often wondered the same thing. I have owned 3 SLRs and none has provided 100% viewfinder coverage. The 95% claimed for my K10D sounds pretty good until you compare the actual images to what was originally framed. That last 5% is HUGE!

Steve

totaly agree here. And on K100D it's even bigger difference...

[Sailor]

I've wondered the same thing - all I know is that my DS2 and K10D don't match the brightness of my LX's. Of course, I may be imagining the difference, but I dimly recall reading that AF cameras generally have truncated viewfinders (?????).

Jer