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LF1 - Maximum Aperture at Various Focal Lengths
So in terms of aperture to 100mm equivalent, it's LX7, RX100, LF1, XZ10, Xf1. It's doing pretty decently for its zoom range with only really the RX100 offering a significant advantage of the 1inch sensor. On paper I'd choose the LF1 ahead of the XZ10 for the extra reach and marginal aperture difference the RX100 and LX7 are different prospects. The LF1 is definitely not all that bad if you found yourself wanting the extra reach for a compact this size where its real competitors are the two aforementioned competitors.
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well thanks. it explains how ro calculate it. but still don't know how to interpret it..
I am sorry...
tkbslc
Forum Pro
The actual aperture sizes are pretty much the same.
LX7 = 17.7/2.3 = 7.4mm
LF1 = 42.8/5.9 = 7.25mm
Which means with equivalent framing, the BG blur is going to be essentially identical. Of course you'll be standing 2.5x farther back with the LF1, but the capability is there.
And while f5.9 sounds scary, remember that is at a focal length that the LX7 can't touch. The LF1 can do f4.7 at 90mm, so then we are only 2 stops down
LX7 has an advantage in low light, yes, but LF1 has advantage in sunlight thanks to the viewfinder, zoom and more portability.
Not as clear cut a decision in favor of the LX7 as some would have you believe.
LX7 = 17.7/2.3 = 7.4mm
LF1 = 42.8/5.9 = 7.25mm
Which means with equivalent framing, the BG blur is going to be essentially identical. Of course you'll be standing 2.5x farther back with the LF1, but the capability is there.
And while f5.9 sounds scary, remember that is at a focal length that the LX7 can't touch. The LF1 can do f4.7 at 90mm, so then we are only 2 stops down
LX7 has an advantage in low light, yes, but LF1 has advantage in sunlight thanks to the viewfinder, zoom and more portability.
Not as clear cut a decision in favor of the LX7 as some would have you believe.
GeraldW
Veteran Member
Those equivalent apertures are only valid for comparing depth of field. For light gathering you need to use the native f/#. The LF-1 does appear to be faster at ISO 100 than the RX100.
GeraldW
Veteran Member
Me too! I e mailed the blogger, and posted above on that. I have not seen a table of actual f/# for the LF1; but a straight line plot on semi-log graph paper shows the LF-1 to be faster at 100 mm than f/4.7. Of course, the actual apertures might not lie on a straight line; other Panasonics don't; but the longer lensed FZ28, FZ35, and FZ150 all have a hockey stick shape which makes then faster than straight line up to full zoom and quite a bit faster at middle focal lengths.
morepix
Veteran Member
It depends on what you need. Two stops is a lot.
And anyway, as the owner of an LX7 with EVF and all, it's pretty clearly a decision in favor of keeping the LX7 and and canceling my LF1 preorder at B&H. Gotta save my pennies in case I get caught up in the excitement about the upcoming GX2.
l_objectif
Forum Pro
morepix
Veteran Member
Louis,l_objectif wrote:
David, please keep your LX7 and when you receive your LF-1, make a comparison of IQ between the two for us!
I have to decide between LX7 or LF-1 for a compact and I am very curious about LF-1 and confused! ;-)
Yes, I'm curious too. Tell you what: Send me $500 for the LF1, and I'll be glad to make the comparative evaluation for you -- to be published here for everyone's benefit and dedicated personally to you in recognition of your selfless generosity. And I'm even willing to keep the LF1 as a keepsake reminder of your goodwill.
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David
www.pbase.com/morepix
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morepix
Veteran Member
I think you meant at 100mm. (?)
GeraldW
Veteran Member
Yes, I did. Thanks for catching that.
l_objectif
Forum Pro
morepix wrote:
Louis,l_objectif wrote:
David, please keep your LX7 and when you receive your LF-1, make a comparison of IQ between the two for us!
I have to decide between LX7 or LF-1 for a compact and I am very curious about LF-1 and confused! ;-)
Yes, I'm curious too. Tell you what: Send me $500 for the LF1, and I'll be glad to make the comparative evaluation for you -- to be published here for everyone's benefit and dedicated personally to you in recognition of your selfless generosity. And I'm even willing to keep the LF1 as a keepsake reminder of your goodwill.
jimr
Forum Pro
and 90mm to 200mm is a lot. An EVF can also be a serious plus as can the smaller and lighter size.....
These are subjective decisions...
Not the clear cut definitive answers that a number of posters make it out to be.
It is almost funny seeing how some make this a clear cut definitive simplistic answer...when it is an individual subjective answer. Both cameras are great choices. The LF-1 is not a Panasonic TZ series camera for good reasons.
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MichaelKz
Active member
Detail Man
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Using available data from DxOMark (RAW-level), DPReview, and Imaging Resource I gathered information allowing comparison of the RX100 and the LF1 with the LX7 at their (shared, 35mm equivalent) Focal Lengths of 28mm and 90mm. Results may vary with in-camera JPG-engines.
Given that Panasonic (like the RX100) already uses a Sony Exmor image-sensor in the LX7 and LF1, and given that an image-sensor the size of the RX100's leads to some lens-system compromises in any camera design, the comparison is a useful one in a general sense.
LX7 - 1.85 Micron pixel-pitch, 9.980928 Mpixels (3468x2736), 34.160 mm^2 active-area, 8.436 mm diagonal, 4;3 aspect-ratio. FL=28 mm, F=1.5. FL=90 mm, F=2.3.
LF1 - 1.85 Micron pixel-pitch, 12.0 Mpixels (4000x3000), 41.070 mm^2 active-area, 9.250 mm diagonal, 4:3 aspect-ratio. FL=28 mm, F=2.0. FL=90 mm, F=4.7.
RX100 - 2.40 Micron pixel-pitch, 20.210688 Mpixels (5504x3672), 116.414 mm^2 active-area, 15.880 mm diagonal, 3:2 aspect-ratio. FL=28 mm, F=1.8. FL=90 mm, F=4.9 (possibly 4.8?).
All comparisons below are at base ISO=80, and assume that the same Shutter Speed is used.
.
LF1 compared to LX7 (FL=28 mm, using minimum F-Numbers):
21.56% more Depth of Field, 0.282 EV lower Signal/Noise Ratio (18%) and Dynamic Range.
LF1 compared to LX7 (FL=90 mm, using minimum F-Numbers):
86.37% more Depth of Field, 0.898 EV lower Signal/Noise Ratio (18%) and Dynamic Range.
.
RX100 compared to LX7 (FL=28 mm, using minimum F-Numbers):
36.25% less Depth of Field, 0.169 EV higher Signal/Noise Ratio (18%), 0.507 EV higher Dynamic Range.
RX100 compared to LX7 (FL=90 mm, using minimum F-Numbers):
13.18% more Depth of Field, 0.659 EV lower Signal/Noise Ratio (18%), 0.321 EV lower Dynamic Range.
.
Comments:
Since the usefulness of having a larger sized image-sensor system depends upon the ability to trade some of the DOF associated with a smaller sized image-sensor system for a higher SNR, the values of the minimum F-Numbers of the RX100 (relative to the image-sensor size, as that translates to system DOF) do not appear to do a very good job of allowing such a user controlled reduction of DOF (via reducing the lens-system F-Number) to take place. As a result, much of the higher performance of the RX100's image-sensor is squandered due to the characteristics of the lens-system.
Also true where it comes to the LF1's lens-system. Note that the LF1's compromised performance is evident even at comparable Focal Lengths, and will continue to degrade further out to FL=200mm.
DM ...
Given that Panasonic (like the RX100) already uses a Sony Exmor image-sensor in the LX7 and LF1, and given that an image-sensor the size of the RX100's leads to some lens-system compromises in any camera design, the comparison is a useful one in a general sense.
LX7 - 1.85 Micron pixel-pitch, 9.980928 Mpixels (3468x2736), 34.160 mm^2 active-area, 8.436 mm diagonal, 4;3 aspect-ratio. FL=28 mm, F=1.5. FL=90 mm, F=2.3.
LF1 - 1.85 Micron pixel-pitch, 12.0 Mpixels (4000x3000), 41.070 mm^2 active-area, 9.250 mm diagonal, 4:3 aspect-ratio. FL=28 mm, F=2.0. FL=90 mm, F=4.7.
RX100 - 2.40 Micron pixel-pitch, 20.210688 Mpixels (5504x3672), 116.414 mm^2 active-area, 15.880 mm diagonal, 3:2 aspect-ratio. FL=28 mm, F=1.8. FL=90 mm, F=4.9 (possibly 4.8?).
All comparisons below are at base ISO=80, and assume that the same Shutter Speed is used.
.
LF1 compared to LX7 (FL=28 mm, using minimum F-Numbers):
21.56% more Depth of Field, 0.282 EV lower Signal/Noise Ratio (18%) and Dynamic Range.
LF1 compared to LX7 (FL=90 mm, using minimum F-Numbers):
86.37% more Depth of Field, 0.898 EV lower Signal/Noise Ratio (18%) and Dynamic Range.
.
RX100 compared to LX7 (FL=28 mm, using minimum F-Numbers):
36.25% less Depth of Field, 0.169 EV higher Signal/Noise Ratio (18%), 0.507 EV higher Dynamic Range.
RX100 compared to LX7 (FL=90 mm, using minimum F-Numbers):
13.18% more Depth of Field, 0.659 EV lower Signal/Noise Ratio (18%), 0.321 EV lower Dynamic Range.
.
Comments:
Since the usefulness of having a larger sized image-sensor system depends upon the ability to trade some of the DOF associated with a smaller sized image-sensor system for a higher SNR, the values of the minimum F-Numbers of the RX100 (relative to the image-sensor size, as that translates to system DOF) do not appear to do a very good job of allowing such a user controlled reduction of DOF (via reducing the lens-system F-Number) to take place. As a result, much of the higher performance of the RX100's image-sensor is squandered due to the characteristics of the lens-system.
Also true where it comes to the LF1's lens-system. Note that the LF1's compromised performance is evident even at comparable Focal Lengths, and will continue to degrade further out to FL=200mm.
DM ...
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morepix
Veteran Member
Not always easy to understand all the details, but it's enough for me to:
In passing, it seems comparison of the LF1 with the Canon S110 is more to the point. And I know your inclusion of the RX100 was simply following the lead of the OP
Thanks.
- Give the RX100 no second thought (not that I had anyway), and
- Continue my cancellation of the LF1 order from B&H and be happy with my fully-equipped LX7.
In passing, it seems comparison of the LF1 with the Canon S110 is more to the point. And I know your inclusion of the RX100 was simply following the lead of the OP
Thanks.
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