From left to right, Lumia 640, Lumia 640 XL, Lumia 830 (and note that I'm starting to regret picking the white 640 XL - it picks up dirt and stains too easily, in this case from being in a black carrier bag....!)
640 XL versus 830
Now, the output resolution from the Lumia 640 XL and 830 is slightly different (effectively 8MP vs 10MP in 16:9 format), but then so is the angle of the optics - whatever I do in terms of cropping, there won't be an exact match-up in the comparators below. I suppose I could have downsampled each to a common resolution (e.g. 5MP) but then that introduces a compromising factor and I want readers to be able to see the raw pixel detail from each smartphone camera. Thus, the crops are as-is, and there will be very slight mismatches in framing in the comparators.
The crops below are all at 1:1 as usual. Rather than push the camera phones to the limit, as usual, I've approached the subjects from the point of view of the knowledgable Lumia user 'pointing and shooting' on a day out, with just a little PureView zooming and here and there, where appropriate.
| Note that the interactive comparator below uses javascript and does need to load each pair of images. Please be patient while this page loads, if you see a pair of images above each other than you've either not waited long enough or your browser isn't capable enough! |
Test 1: Landscape, sunny
Looking across the main lake at Hestercombe Gardens. Here's the overall scene, for context:
In case you want to grab the original images to do your own analysis, here they are, from the Lumia 640 XL and Lumia 830, click the links to download. And here are detailed 1:1 crops, just wait to make sure the page has fully loaded and then use your mouse or trackpad pointer to compare the images:
An easy scene to shoot, of course, with abundant light. There's very little to choose between the two shots, showing how close the sensor and optics are in the 640 XL to those in the 830.
Test 2: Medium distance, sunny
An attractive orangery, with plenty of detail, and with the challenge of a well lit face and one in shadow. Here's the overall scene, for context:
In case you want to grab the original images to do your own analysis, here they are, from the Lumia 640 XL and Lumia 830, click the links to download. And here are detailed 1:1 crops, just wait to make sure the page has fully loaded and then use your mouse or trackpad pointer to compare the images:
A very slight IQ win for the 830 here, but it's debatable. The white on the door/window is overdone in the 640 XL shot and arguably too creamy in the 830's, but there's really not much in it overall.
Test 3: closer still, sunny
Part of my dad's garden, with plenty of natural and pretty detail. Here's the overall scene, for context:
In case you want to grab the original images to do your own analysis, here they are, from the Lumia 640 XL and Lumia 830, click the links to download. And here are detailed 1:1 crops, just wait to make sure the page has fully loaded and then use your mouse or trackpad pointer to compare the images:
Again, a very slight IQ win for the 830 here, but it's debatable. If it wasn't for the resolution difference, I'd swear that these two phones had the same lens and sensor! Maybe the use of Lumia Camera 5 and its own way of processing and encoding JPGs is the dominant factor here. Both photos show over-blown highlights, by the way, I wish I could go back and turn 'Rich Capture' on!
Test 4: Dusk
A church scene just before it was dark. The light levels were lower than you might think from the shots below, it was really errr... dusky, you can tell from the visibility of the floodlights on the front face. Here's the overall scene, for context:
In case you want to grab the original images to do your own analysis, here they are, from the Lumia 640 XL and Lumia 830, click the links to download. And here are detailed 1:1 crops, just wait to make sure the page has fully loaded and then use your mouse or trackpad pointer to compare the images:
Unsurprisingly, the Optical Image Stabilisation in the 830's camera enables the shutter to be open longer (it chose 50% longer, around 1/20s in this case) and thus more light gets to the sensor, plus the stabilisation helps keep things very crisp. I did a pretty good job of keeping the 640 XL steady, most users wouldn't achieve as respectable a result.
Verdict (part 1)
The takeaway from the four test shots above is that the 640 XL's camera punches above its weight, equalling that in the 830 except when light is so low that OIS comes into play.
However, I'd also had questions about the 640's camera, i.e. that in a £90 (on pay as you go) handset. Surely the 8MP unit here would be inferior? Taking two test shots, I looked again at 1:1 crops, but this time the gap in resolution was high enough that I felt I had to do an initial resample, taking the 10MP (in 16:9) results from the 640 XL down to the 6MP (again in 16:9) from the vanilla 640. Needs must, etc.
Neither test shot are that interesting as photos go, but this section of the article is something of an addendum, so....(!)
640/640 XL test 1: Sunny landscape
Looking out over the gardens and fences from my suburban first floor, I was focussed on the distant house roof. Here's the overall scene, for context:
Here are detailed 1:1 crops, just wait to make sure the page has fully loaded and then use your mouse or trackpad pointer to compare the images:
Looking closely, there's an extra clarity to the 640 XL's shot, mainly due to the ZEISS lens, though I'll admit that I'm being a bit picky here. Though given that the 640 XL's shot was already downsampled, the extra detail in the original would take it quite a bit further than the 640's camera.
640/640 XL test 2: Indoor low light macro
The acid test, when light conditions get challenging. Here's the overall scene, for context:
Here are detailed 1:1 crops, just wait to make sure the page has fully loaded and then use your mouse or trackpad pointer to compare the images:
The larger optics, sensor and ZEISS lens again show their worth, with better colours and more natural detail even in this low light test. Plus even a little bit of 'bokeh', usually associated with high end camera phones. In contrast, the camera in the Lumia 640 is producing results that aren't terrible, but are definitely at the lower end of what we're used to seeing in these camera comparisons on AAWP, with noise, muted colours and artefacts.
Verdict (part 2)
I do have a mental model of how the cameras in all these phones should perform, given specifications and characteristics, so it's gratifying when test results bear everything out - and in visual form that anyone can see on the page. The Lumia 640's 8MP camera produces very decent results in good light, as you might expect, certainly better than many competing £100 phone cameras, but when the light fades its limitations are more obvious. It's certainly a step down from the camera in the 640 XL - the larger sensor and better optics play a big part in the imaging pretensions of the budget phablet.
So physics wins - again. With the image processing and camera software identical between the test devices, looking at all the photos in my tests over the last few days, I'd score the three camera phones (across all scenes and conditions) at:
- Lumia 830: 75%
- Lumia 640 XL: 68%
- Lumia 640: 55%